Gas Expert Evidence - Wednesday 14th July 2021 (2/2)

Full transcript

00:00:42 would you ask mr hancock's to come back in please

00:00:55 thanks to cox

00:01:17 all right ready to carry on yes good thank you yes mr scranton yes thank you yes we were part way through discussing trio's replacement design one in particular about the ventilation aspect

00:01:28 particular about the ventilation aspect of it

00:01:29 of it and i want to take you to an email now if we can look at cad 6038

00:01:39 this is the the second email that simon boygill sends following his second survey that he had done and at the bottom of the page under the heading ventilation g5

00:01:53 under the heading ventilation g5 we can see that he said if we could move down the page a little um once the pipe work is installed the riser system could be segregated from the mechanical

00:02:05 could be segregated from the mechanical air extraction by being boxed in there is a route out to fresh air through the basement and would assume a route out through the top floor

00:02:15 top floor no access to roof as locked so that's what the surveyor was saying about the ventilation now um just to be clear mr boiger was a surveyor wasn't he

00:02:27 surveyor wasn't he i believe so would you have expected the trio designers to have really scrutinized in detail the route that was being proposed by mr boygill to check that it really was

00:02:38 boygill to check that it really was compliant with igem g5 in particular yes yes and we've been looking before the break at what igem g5 says about the

00:02:49 at what igem g5 says about the ventilation can we just look at a couple of diagrams that are also in that same section of g igem g5 if we go to rhx

00:03:03 seven zeros five back subactive igem g5 and look at page 54.

00:03:14 this is um figure 18 that we get in that standard and we can see the figure title at the bottom figure 18 internal screwed or

00:03:25 bottom figure 18 internal screwed or welded network pipeline passing through a protected shaft ventilated directly to outside air and can we see the ventilation um by

00:03:36 and can we see the ventilation um by those little they're kind of pale green or pale yellow vents that are showing here yes so if you're putting the riser up the stairs

00:03:47 stairs um this is giving you an indication in igem g5 of how you could then ensure that's vented direct to the outside is that correct that's correct yes

00:03:59 and then if we look on to figure 19 on the next page um this is titled figure 19 internal screed or welded network

00:04:11 internal screed or welded network pipeline passing through a service duct on an outside wall which is fire stopped to each level so is this showing us what the ventilation arrangements need to be if it's effectively passing through a

00:04:23 if it's effectively passing through a series of compartments on its way up the building yes and what you're looking for for each compartment would be event at top and bottom is that correct that is correct where it goes through

00:04:35 goes through and so um can we take it is this a good way of looking at it that the diagram before

00:04:41 before was what we should have been looking at in terms of certainly the bits on the stairs and up to the top of the stairs and this diagram was perhaps more relevant to what was going on at the lower levels of the tower between the basement and the bottom of

00:04:52 between the basement and the bottom of the stairs is that correct yes you could take the principles of those two drawings

00:04:57 drawings and when you went to grenfell tower that's effectively what you were looking for when you were assessing whether the ventilation requirements yes ventilation arrangements were compliant with igem g5

00:05:09 compliant with igem g5 yes yes thank you now just thinking back to mr boiger's statement and what he said about this route he said that there's route to fresh air in the basement

00:05:20 fresh air in the basement do you agree with that fresh air was getting into the basement yes

00:05:27 yes because there were combustion equipment there in the plant room yes and that's what that fresh air was for

00:05:36 because the plant room is a fire compartment in its own right yes which means that the roof of the basement needed to be

00:05:48 roof of the basement needed to be effectively a fire compartment roof yes so

00:05:56 if we assume that mr boigel is thinking that air could automatically go from the basement up through the

00:06:08 from the basement up through the riser shafts um he was mistaken right yes um just to make good the point you said earlier about the fact that there is some fresh air

00:06:19 the fact that there is some fresh air provision to the basement um if we could look at a picture on that that's tri7050

00:06:27 this is a picture from that actually is in your report yes and is it right that on the very far left of the picture where the figure where we see 10 inches

00:06:39 where we see 10 inches written we can see behind it a little plinth is that correct yes and is that effectively like a honeycomb

00:06:47 honeycomb plinth that is giving ventilation to the basement

00:06:51 basement i believe it is yes but despite that you don't think that there would have been sufficient natural ventilation at the bottom of that shaft is that right once it penetrated the roof of the

00:07:03 once it penetrated the roof of the basement and went upwards um

00:07:08 it's a bit different to that um

00:07:12 the the thing is to my understanding about the

00:07:15 about the the basement being a place of special fire hazard yes it has to be compartmentalized from the rest of the building yes from fire compartment

00:07:26 building yes from fire compartment perspective you couldn't open up excuse me the roof of the basement to the utility shaft yes uh that had to be sealed as a fire

00:07:39 yes uh that had to be sealed as a fire compartment yes um so really had that riser being compliant it needed to somehow find

00:07:48 find open air at low level so coming out perhaps at ground level yes or it is possible i suppose and and i'm speculating here yeah that

00:07:59 and and i'm speculating here yeah that mr boigel thought that a duct could be a field installed from the bottom of the riser compartment yes through the

00:08:12 compartment yes through the um the basement to that um air intake unit yes um and possibly give uh effectively the separate

00:08:23 separate duct yes the sealed docked ventilation for the

00:08:27 for the riser cover but we've not seen any drawings or sketches or even correspondence with that because that would have been a major um

00:08:39 major um structural changed the building yes yes thank you

00:08:42 thank you yes there was some suggestion i think from um mr dolan yesterday that that might have been the intention but i think what you're confirming and he to be fair he accepted was that's never been written down or

00:08:55 was that's never been written down or documented or outlined in a drawing that they might have been intended to be the separate duct running through the basement and then up to fresh air yes that's right and it's pure speculation

00:09:06 speculation on my part at any rate yes as to what he meant yes

00:09:10 meant yes and and what you seem to be saying is that that would be major works and if that really had been intended you would have expect to have seen that identified from the outset of this design process oh yes

00:09:21 design process oh yes or certainly yes if you come up after the decision to box in then there would have had to have been a drawing proper drawings yes thank you um and then

00:09:34 yes thank you um and then as the riser comes up the building from the basement through the lower two levels passing the utility shaft and through the store next to the community room

00:09:45 to the community room um it's right isn't it that each of those was effectively a separate compartment from the stairs yes um and so is it right that each of those had to be completely fire

00:09:56 each of those had to be completely fire stopped

00:09:57 stopped top and bottom well they were yes yes yes but also then you've got this competing

00:10:05 competing requirement to have their own ventilation at top and bottom of the compartment is that correct yes now we can see some images of what you saw when you went to site if we go to your first report again at

00:10:16 if we go to your first report again at rhx 6012

00:10:18 rhx 6012 page 30.

00:10:22 there's three pictures at the top here that you've set out in the the your report of the riser entering

00:10:29 entering so we can see on the far left the riser entering the utility shaft at ground floor

00:10:34 floor and going through that shaft then then a picture of it going up that shaft and exiting the utility shaft at second floor

00:10:43 floor now did you see any sufficient ventilation at that point no

00:10:51 now we also understand that the riser went through a store next to the community room again did you see any event did you see sufficient

00:11:02 sufficient evidence of ventilation at that point no

00:11:07 now it was said yesterday and is all evidence by mr dolan that the louvres at ground floor level to one of the doors provided some ventilation at this part

00:11:18 provided some ventilation at this part of the route let's just look at a picture of that it's at cad

00:11:24 five zeroes sorry six zeros 54

00:11:30 at page 13.

00:11:34 this these were some of the photos taken by mr boigel during his survey and he he pointed to that and he said well you can see louvres on that effectively hatch or door

00:11:46 on that effectively hatch or door that would have provided some i think it's called the indirect ventilation now did you see that when you when you went to the tower i certainly

00:11:57 when you went to the tower i certainly don't recall seeing that yes i am quite certain that if i had i would have taken a photograph of it if i had seen it in february yes if i'd have seen it when i was accompanied by the

00:12:07 the mps photographer i would have asked him to take a photograph of it yes looking at that photograph now what is your understanding of where the riser actually

00:12:17 actually goes through the building in in comparison to where that louvre door is i don't know where that louvre door is right i don't even know if it's actually on the riser shaft that where the gas pipe

00:12:29 the riser shaft that where the gas pipe was put

00:12:30 was put right yes so you took photographs in your report of of the riser going up each compartment of the building and you didn't ever come across that door as part of its route

00:12:42 door as part of its route and i have checked the corgi report and there's no mention of any louvre doors or ventilation at

00:12:55 louvre doors or ventilation at levels one and two right yes and just going back to the store next to the community room i think the suggestion was yesterday that that store door might be opened and

00:13:08 that that store door might be opened and closed

00:13:09 closed and thereby provide some form of ventilation i think mr dolan accepted that wasn't a louvre door in your view is that acceptable as a

00:13:20 in your view is that acceptable as a a method for ventilation no the shaft if you're

00:13:24 you're going to start talking about indirect ventilation you've got to be effectively you want people going in and

00:13:31 and out regularly door movement which creates

00:13:36 creates air movement itself and a storeroom no doesn't do do that that's opened occasionally yes so

00:13:43 so if we take the stairs and the stair doors is that the kind of movement that you might be expecting to create that air movement yes it's the bare minimum but it's

00:13:52 but it's [Music]

00:13:53 [Music] it's that sort of yes there where you again people coming in through the entrance to the building frequently whether they're going to the stairs or whether they're going to the lift

00:14:03 lift they're going to be coming in and out probably over a 15 18 hour time period yes yes

00:14:13 yes yes and mr boigel also mentioned in his email he says there was potentially ventilation at the top of the shaft through the roof vent although he said he wasn't able to access that in your view was the roof ventilation

00:14:27 in your view was the roof ventilation of that design design one was that adequate in your view probably there probably would have been enough uh high level ventilation yes yes yes because you've got an open vent at the

00:14:38 because you've got an open vent at the top of the stairs so even though you don't see a drawing that actually tells you beyond level 23 what was to happen

00:14:46 happen you're not critical of that no no thank you

00:14:50 you but i think to summarize because of the reasons you've just outlined about these lower levels you are clear are you not that um the ventilation

00:15:01 ventilation arrangements were inadequate for this first design of the riser correct yeah

00:15:09 now um just in terms of how the design developed if we go to tri60263

00:15:25 here we can see um a drawing which was for

00:15:29 for the first version of the design and if we look at that inset box in the middle

00:15:35 we can see that the intention was to box in the pipe work on the lobby side where it where they've got the laterals to each part of the stairs is that your understanding yes

00:15:47 stairs is that your understanding yes and was that essentially to deal with compartmentation because you needed to compartment off the gas pipes in the lobby from the rest of the lobby

00:15:58 lobby um

00:16:01 well that's the view they took because of mistaking the smoke control system with mechanical ventilation right so um just to make that good

00:16:14 right so um just to make that good why are you saying that the smoke control system wasn't a mechanical ventilation i understand the mechanical ventilation system basically to be operating most of the time

00:16:22 the time right and not if there's just a fire or if the smoke i see so you wouldn't have had the same concerns that they had about separating out those pipes from that lobby

00:16:34 out those pipes from that lobby um at first sight no but i'd have wanted confirmation from the building owners precisely what that system was yes okay thank you and

00:16:45 that system was yes okay thank you and um it's right isn't it that this design from the outset required oversized holes to be in

00:16:49 to be in place between the stairwell and the lobby to enable there to be ventilation of that that boxing in back to the stair

00:17:00 that that boxing in back to the stair is that correct that is what they have done yes yes i appreciate you drawing a distinction between what they should have done and what they did do i think i was

00:17:11 and what they did do i think i was asking

00:17:12 asking what you think they were trying to do in this um

00:17:16 this um just thinking about um ventilation first of all

00:17:21 of all um do you consider that this was an appropriate ventilation strategy at this point

00:17:27 point in particular would you have been satisfied that any minor gas leak down the end of one of those

00:17:34 those um boxes in the lobby would have been adequately addressed by the air flow that you get through the stairwell well

00:17:49 one it's you've got a i suppose a smallish volume i don't know what the volume is

00:17:55 volume is there were no calculations yes

00:17:59 the general rule of thumb for if you've got a branch off from a shaft is to say anything under you probably get away with something like that if it's

00:18:10 like that if it's less than one cubic meter well if you like effectively the the volume of a an oven and that's the sort of volume you're talking about i'm not sure

00:18:21 talking about i'm not sure that the volume of the ducting in the lobby to surf that too yes um

00:18:30 was quite possibly over one cubic meter yes so i've got my doubts that that would have worked yes yes and and you said at the outset

00:18:41 yes yes and and you said at the outset of that answer there was no calculations should there have been calculations in my view yes yes if they're going down that sort of route yes yes and and it's right isn't it that

00:18:52 yes and and it's right isn't it that once you

00:18:53 once you extend thinking forward to the fact that they were going to use this route to replace all of the flats gas supplies you'd have even more boxing in in due course oh yes yes and far larger

00:19:06 oh yes yes and far larger better term dead space yes that's the risk the theory as i see it that they were trying to to do was to allow the natural

00:19:18 to do was to allow the natural buoyancy ventilation going up the riser to pull out or cause a turbulence and to pull out any gasoline mixture from the the ducting yes um you can do that for a

00:19:32 the ducting yes um you can do that for a small volume but the larger the volume the more problematic that becomes yes so even taking this portion of the building and what was going on in the

00:19:43 building and what was going on in the stairwells it sounds like you were very doubtful about it as a ventilation strategy

00:19:48 strategy at this point as well yes um and you tell us in your first report that igem g5 requires a risk assessment to be carried out in respective designs

00:19:59 to be carried out in respective designs is that correct that is correct and in general terms can you just tell us what's good practice in terms of what a designer should do when they conduct a design risk assessment

00:20:10 well basically g5 has got an appendix appendix 3 which discusses different aspects the network pipeline

00:20:21 different aspects the network pipeline the meter installation installation pipe work the sort of things to be considered and i've also in my report

00:20:33 and i've also in my report done a bit of a checklist as to what i think

00:20:36 think should be uh considered in the design risk assessment it's not a tick box exercise it's basically saying consider this does it apply how are you dealing and if yes

00:20:49 dealing and if yes how are you dealing with it yes uh for example i'd always have on that checklist flooding because in some circumstances that could be an issue down at the basement level in this case

00:21:02 down at the basement level in this case that could be signed off as not applicable but at least be considered yes yes and are there particular risks for gas supply to multi-occupancy buildings

00:21:15 supply to multi-occupancy buildings um

00:21:18 the there are risks if you have got antisocial behavior possible um if somebody decides to um

00:21:31 somebody decides to um leave the flats taking their cooker with them

00:21:36 and not disconnect not getting it properly disconnected

00:21:42 and there's a subsequent leak within the flats you could actually um create an explosive atmosphere yeah with which has a significant

00:21:53 yeah with which has a significant societal risk um i've come across something similar that in my own experience but um there's the thing to bear in mind about

00:22:04 the thing to bear in mind about multi-occupancy buildings is that if you do something stupid or as a consumer does something stupid then it affects not only them but other people or other units within the block of flats yeah yeah

00:22:18 within the block of flats yeah yeah and would you have expected trio to have done a full design risk assessment for its design its first design of the riser replacement at grenfell oh yes yes as a matter of course yes

00:22:30 yes as a matter of course yes now um just some questions about the meter position for a moment because we know that the original meters had to be moved for this design from the kitchen cupboard

00:22:41 design from the kitchen cupboard to a location closer to the front door and in your report you say these meters were repositioned in a place which you have said was this

00:22:52 which you have said was this in the soul means of escape it was adjacent to the sole means of escape yes um now mr dolan yesterday um was saying that

00:23:05 yesterday um was saying that the and i'll take you to some photographs in a moment the the little separate cupboards into which these meters were installed were treated by the trio designers at effectively a separate room and not in the means of escape in your opinion

00:23:19 in the means of escape in your opinion is that a

00:23:20 is that a reasonable stance for kate for trio to have taken no it was a it was a cupboard adjacent opening onto the sole means of escape from the flat

00:23:32 the sole means of escape from the flat if you look at the paragraph in g5 which deals with this particular issue

00:23:40 and reason in its entirety you need that cupboard because it's not a bedroom

00:23:49 bedroom it's not a study or a living room it's a cupboard might be a bigger biggest cupboard but it's a cupboard it's got no windows it's

00:24:02 basically it opens onto that um the hallway there um it's

00:24:13 um it's cannot

00:24:16 there's no evidence that it is 30 minutes fire resistance yes et cetera we'll come to that yes um i think the part of igem d5 you might be referring to if we go to rhx705

00:24:29 referring to if we go to rhx705 and look at page 38

00:24:35 is it paragraph 5.2.2.4 uh five two three one whoops sighting meters when we thread the solid scope routes within individual dwellings

00:24:47 scope routes within individual dwellings if it is proposed to install a meter in a sole means of escape within an individual dwelling yes the meter shall be enclosed in a box yes cupboard

00:24:59 cupboard or other compartment which may open onto the sole means of escape from within the individual dwelling which is at least 30 minutes fire resistant

00:25:10 resistant and which has a self-closing door yes or fitted with a thermal cut-off device yes and just to be clear those provisions certainly were not satisfied at

00:25:22 certainly were not satisfied at grenville tower were they and you've got a number of photographs in your report where you can see open cupboards or cupboards with a hinge which could be removed very easily

00:25:33 hinge which could be removed very easily they weren't 30 minutes fire resistant were they

00:25:36 were they no evidence of that they certainly didn't look it to me a 30 minute fire resistance door is fair to say he's heavy-ish

00:25:47 fair to say he's heavy-ish yes requires a little bit of oomph to remove it

00:25:50 remove it and you didn't see evidence of tcos either no no and as i as we understand it from mr dolan's evidence they weren't attempting to comply with this because they had decided that it wasn't in a soul

00:26:01 decided that it wasn't in a soul means of escape and um i'm just just wanting to tease out from you exactly why you say it's in a sole means of escape by reference to this standard

00:26:12 reference to this standard um it's covered in my view you could argue if mr dolan is not a cupboard

00:26:19 cupboard it's not a box but it is an other it is an other compartment according to roots are the compartment yes which opens onto the sole means of escape yes so what

00:26:32 the sole means of escape yes so what you're saying is this standard is envisaging that you could have a cupboard or other compartment immediately adjacent to the means of escape

00:26:40 escape but nevertheless it's got to have those features to be satisfied yes yes well i suppose in part there's a question of construction about what's meant by

00:26:50 meant by inner soul means of escape because i think what uh we were shown was

00:26:57 was a picture of a hallway in a flat with this uh area i'll try and use a neutral word off the hallway yes and

00:27:09 off the hallway yes and i think mr dolan's evidence was they regarded that area as not being in the sole means of escape yes let's look at that picture would that help

00:27:21 that picture would that help um if i get it up at met 3016651

00:27:28 is that is that the the image you were thinking of mr chairman yes i think it probably was or at least one of them yeah um so i think you as i understand it the

00:27:39 um so i think you as i understand it the area in which that we can see the meter is through an arch which itself is open to the uh

00:27:50 the uh always leading to the front door yeah that's right yes yes

00:27:56 yes yes that's as i understand it what mr dolan was saying but this is very much the exception to what was there at grenfell tower in the sense that it was got the arch the other photograph i've

00:28:09 got the arch the other photograph i've got

00:28:10 got in the report yeah showing the door let's go to that met three zeros one

00:28:18 one six five five eight

00:28:26 is that it there that's it there yeah and and can you explain why you say that it's right can we just understand what we're looking at there is that is that the front door to the flat that

00:28:38 is that the front door to the flat that front door of the flats sir is on the right oh yes i can see it i'm sorry

00:28:43 i'm sorry that's to number 52 so there's um an area behind the the door that's partially opened yes that is the the door to the cupboard right so that is the

00:28:54 is the space in which the meter was located yes well then there's as i say i suggest there's a question about whether the meter was in the sole route of escape well that he was in

00:29:06 route of escape well that he was in which opened onto well all right i mean we can just discuss this at length but yes i was moved to um raise the point because of the wording of

00:29:17 because of the wording of five yes

00:29:20 five yes that particular paragraph of paragraph five

00:29:24 five um just to test the argument that the meter was being installed in the sole means of escape it's a bit ambiguous that uh well

00:29:35 it's a bit ambiguous that uh well certainly the intention in that uh which exercised our minds significantly for a long period was to basically say you had a cupboard like that and it was

00:29:49 you had a cupboard like that and it was the the door to that cupboard needed to be self-closing 30 minutes fighting resistance well in the end the intention of the draftsman has to be collected from the

00:30:00 draftsman has to be collected from the language he uses because the third party reading it won't know that really yes anyway there it is thank you but just in terms of how the industry interpreted that

00:30:11 interpreted that uh part of igem g5 is it your understanding that within the industry it was usual to interpret it as including a cupboard like that which led

00:30:22 including a cupboard like that which led on to a means of escape yes right

00:30:27 and just thermal cut off devices we we saw that in the igm standard it said you can either have a compartment that's 30 minutes fire rated with a self-closing door or a thermal

00:30:38 with a self-closing door or a thermal cut-off device just help us as to exactly what a thermal cut-off device does effectively it is a device which will shut off the gas supply

00:30:53 which will shut off the gas supply when the it reaches the temperature at all just above 95 degrees c yes

00:31:01 and um is it right that these tcos can be combined with something called an excess flow valve and hfv what's what's an excess flow valve

00:31:11 valve an excess flow valve is a device so that if there is for example an open end in the in the flat yes

00:31:22 in the in the flat yes the flow that's going through the pipe will be much greater than is normally

00:31:30 accommodated by the meter and so the pressure differential across the

00:31:36 the excess flow valve increases and so a spring then closes the valve yes

00:31:43 yes it's an automatic means of shutting down the supply yes thank you now just looking a little bit more at the design documentation that trio produced if we go to tri60369

00:31:57 if we go to tri60369 this is the cdm design risk register for the first design which is dated the 15th of november 2016

00:32:09 is dated the 15th of november 2016 and we understand this is the assessment that that was done for the for the first design um you described this in your first

00:32:20 um you described this in your first report and i'm not going to take you through all the detail of it because i did it

00:32:23 did it we did that with the factual witnesses um

00:32:26 um but um you describe this in your first report as

00:32:29 report as generic can you just explain what you mean by that virtually everything that's on there is about work carried out outside in the highway

00:32:43 outside in the highway the majority of work that trio does on the replacement program is the replacement of iron mains in the street yes and all these things

00:32:55 in the street yes and all these things start talking about open trench insertion open cut

00:33:02 pressure proximity pressure reduction installations

00:33:08 hazards from commercial industrial high street

00:33:12 street underground plant these are all external issues and tanned on the bottom you've got this reference to occupancy building yes and at the bottom

00:33:23 occupancy building yes and at the bottom we can see that what they do is they give it a score and if it's above um 18 or above um then it's a full design risk

00:33:34 um then it's a full design risk assessment is required and if it's below that and this was just below at 17 then no full design risk assessment is required

00:33:41 required um in your view is that an acceptable approach

00:33:45 approach not for multi-occupancy buildings no and we can see at the bottom that there was provision for a manual override right at the bottom of this form there was a tick box where you could manually

00:33:56 tick box where you could manually override the scores that this had come up with

00:33:59 up with and they didn't do that for the first design

00:34:03 design would you always advocate um conducting a full design risk assessment for a gas riser design in a multi-occupancy building yes yeah and that's because of the complexities

00:34:14 and that's because of the complexities you've just been explaining to us yes yes thank you and i think it follows from your answer that therefore this was a case where there needed to be a manual override

00:34:24 override is that right now we know that there was then a change of design on around the 21st of march 2017 it was discovered that the riser

00:34:35 2017 it was discovered that the riser had been built with flanged joints not screwed

00:34:38 screwed joints and that was a significant departure from trio's first design is that correct yes yeah would you have expected that the project manager at trio would have

00:34:50 the project manager at trio would have consulted a senior designer before changing to flanged joints yes it was a design variation yes and that the impact of that change should have been fully reviewed is that

00:35:02 should have been fully reviewed is that is that right yes he certainly should have been

00:35:06 have been discussed and documented may only been a short note but he documented within the design process i think in fact the evidence was not that it was a design

00:35:17 that it was a design change by the trio designers but then it was a

00:35:20 was a a design change introduced on site on site yes by the operatives who are doing the work yes that's why i think i sorry i meant to say should it have been

00:35:30 have been considered by the trio designers sorry that's what i understood the question to to be i wasn't saying was it well i think what happened i think what we were told was that

00:35:41 think what we were told was that the the site manager or whoever was responsible didn't pick up this change until it had happened yes because he couldn't in one sense but until it was well established

00:35:52 until it was well established and it was not a design change introduced by the trio designers it should have been approved or stopped by the tree removed perhaps yes yes

00:36:06 removed perhaps yes yes yes sorry i think i said that the impact of that change should have been fully reviewed

00:36:13 reviewed and by just trying to get a sense of what the process ought to have been at that point what was the practical the significant practical effect of that change to flanged joints

00:36:28 um

00:36:32 well a joint is a joint um

00:36:41 the

00:36:45 possibly speeded up the

00:36:49 connection of the the lateral to the outlet from the riser yes um but in terms of the compliance of the design what effect did that have the fact that they were flange joints not screwed

00:37:01 they were flange joints not screwed joints or welded joints my own view is that a flange joint in fact is no more uh risky than a screw joint right

00:37:13 uh risky than a screw joint right um in fact i think i could point you to data that shows it to be less uh have a lower failure frequency right but um

00:37:24 failure frequency right but um so that would be my my personal view we just tend to talk in terms of screwed or welded

00:37:30 welded um one could argue that's a

00:37:35 sloppy language uh because we're talking uh

00:37:40 uh spanish joints are generally found often with valves right um and if we look at the revised drawing for this five zeros one two two three this is the

00:37:52 five zeros one two two three this is the revised drawing that was done for the design we can now see that what they've done is if we expand this so we can see that the photograph and the the sketch in the

00:38:04 the photograph and the the sketch in the middle

00:38:06 middle we can see that the boxing in is now extending into the stairwell is that correct

00:38:12 correct yes and i think mr dolan confirmed that the boxing in was also then intended and did in fact because they did this piece of work went up the lateral as well in in the stair

00:38:23 up the lateral as well in in the stair is that correct yes yes um and then we can see from the photograph above it

00:38:31 above it where the boxing in was to go that it was to be two-hour fire-rated boxing and there's intumescent vents that are shown

00:38:39 shown there now was the use of intermediate vents compliant with gas industry standards at the time no can you explain

00:38:50 no can you explain why not well essentially i don't see what

00:38:59 well first of all we don't mention them at all in g5 and they're only basically there if you're looking at an internal uh ventilation source um

00:39:12 the and we we want certainly for the ventilation you want it to be to outside or

00:39:18 or from outside um in this particular instance here particularly given that you're by putting your boxing in

00:39:29 you're by putting your boxing in the riser and effectively making a protected shaft within a protected shaft yes as i i would think it that's actually defeated by putting

00:39:41 that's actually defeated by putting international events there right yes um certainly when i visited sites i saw no evidence

00:39:52 evidence of any intermission vents having been fitted

00:39:56 fitted yes

00:39:59 i appreciate mr dolan said yesterday that the

00:40:02 that the intention was to go back and cut them in

00:40:08 but um again we we're back to what is the purpose of those vents what are what are the calculations based on yes

00:40:19 what are the calculations based on yes what sizes were they what function did they serve yes and you've not seen any of that at all no

00:40:27 no now we heard from mr dolan yesterday that the intention was that there was to be boxing in of the entire pipeline including at lower levels

00:40:38 pipeline including at lower levels through the community center the utility shaft

00:40:40 shaft and into the basement and out now we've we've talked already about the ability to box in through the basement so leave that to one side

00:40:52 so leave that to one side in your view was it practical or feasible

00:40:56 feasible to have boxed in through those compartments at lower levels to create so within the cupboard in the community room and within

00:41:04 within the riser shaft that you photographed before could you have created boxing in to make that it's a separate shaft at those levels i don't think that you still got to generate

00:41:18 an air movement in you've still got to get vent air from outside and i don't see where that's coming from yes

00:41:26 yes um and how much work would have been involved in actually doing that boxing in

00:41:30 in in your view i think a significant amount

00:41:33 amount yeah and just to be clear you've not seen any documentation have you that suggests that that was the intention

00:41:41 intention no i haven't

00:41:46 um and just to be clear you would have expected would you a gas engineer a reasonably competent gas engineer to have analyzed the ventilation by

00:41:57 ventilation by um performing bespoke calculations would they be bespoke calculations for each compartment where it was a compartment like at lower level or would the calculations be for the

00:42:08 or would the calculations be for the whole shaft um a couple of ways going around it the default position is to try and get to

00:42:18 to event sizes that comply with table one ps8313

00:42:23 ps8313 or the table that's in igem g5 which is slightly different um failing that it means um

00:42:34 failing that it means um doing some as i say bespoke um calculations the sources for that is a british ps5925 or the more specific hazardous area

00:42:47 or the more specific hazardous area calculations um from igem sr25 right so there are standard industry ways of performing these calculations is that right um

00:42:58 that right um yes for if you've got those sort of cuffs that requires a bit of ingenuity but it can be done yes and is it right that one of the other potential problems you've identified with this ventilation

00:43:09 you've identified with this ventilation strategy is whether it would have been adequate once it was all all boxed in yes um let's just look at a photograph you you've got in your first report um rhx6012 at page 195.

00:43:25 figure 92 this is a a figure a photograph taken by someone standing on one of the stair landings and looking down onto the vertical riser and the red ring is a sleeve is that correct

00:43:37 ring is a sleeve is that correct that's correct and then that space between the sleeve and the pipe would an engineer call that the annulus yes and if we go on to the next page

00:43:49 yes and if we go on to the next page page 196

00:43:51 page 196 you have marked up a photograph with some red lines yes and you've got a label concrete floor impeding the flow of air yes you say flow um can you just explain

00:44:03 yes you say flow um can you just explain what your concern was about the way in which these pipes would go through the stair floors right if you go back to approve document b uh

00:44:14 approve document b uh i think it's clause 841 yes i think

00:44:20 there is a requirement there that there shouldn't be any impediments for the air flow from bottom to top yes uh in the protected shaft and effectively what

00:44:32 effectively what that arrangement i'm suggesting it should be

00:44:36 should be cut out that concrete there so that there isn't an impediment or impedance impedance to the um flow of gas or flow of the airflow from

00:44:47 flow of gas or flow of the airflow from bottom to top yes i think the bit of adb you're referring to is where it says any extension of the story floor into the shaft

00:44:54 shaft should not compromise the free movement of air over the entire length of the shaft that's the one yes it's 8.41 over approved document b on page 81. and and so i'm sorry can i just

00:45:06 and and so i'm sorry can i just interrupt you does that mean you you first of all you have to decide what the size of the shaft or the enclosure needs to be don't you well it certainly if you've got a

00:45:19 well it certainly if you've got a a small shaft or small with a smallish cross-sectional area then effectively you need to make sure that you um

00:45:30 you need to make sure that you um minimize any impediments or any obstruction at each of the floors well i'd rather assume you did it the other way around that you decided how big the shaft we'll call it a shaft but it's a box

00:45:41 we'll call it a shaft but it's a box really isn't it what the size or the area of the box needs to be um and then you can decide how much concrete if any you need to cut away

00:45:52 concrete if any you need to cut away is that is that how it works no it's more the other way i'll take in this instance you're creating a shaft based on i suppose they're

00:46:05 shaft based on i suppose they're minimizing the area that's been taken up by this protected shaft within the dirty shaft and um when you get to a shaft of that sort of cross-sectional

00:46:17 a shaft of that sort of cross-sectional area the size of vent at each end should be the side the second cross-sectional area is the size of the shaft

00:46:28 of the shaft right

00:46:34 yes and so going back to this the arrangement that was put in your view is that was not compliant with approved document b is that correct yes yes i think the

00:46:46 is that correct yes yes i think the concrete and let's face it this is very much an afterthought than boxing in this pipe if you'd cut out the concrete

00:46:57 out the concrete across the whole area of the box you wouldn't need the sleeve would you because that you wouldn't it was redundant

00:47:05 redundant you you could perhaps just as well have made the

00:47:08 made the since you've got to break through you could have drilled instead of what we would tell was a three inch uh hole you could have drilled a four inch hole was that even big enough and

00:47:19 inch hole was that even big enough and just

00:47:19 just fit the boxing around the four inch hole um

00:47:24 um well given that the the boxing in and therefore creating this protected shaft within the protected shaft the same as an afterthought um so

00:47:39 um so i think the process they would have had to have gone through um would involve cutting out otherwise if you started from scratch yeah

00:47:48 yeah then you'd say right you'd have a what the pipe going up there was a three inch so you

00:47:58 are probably talking about a an eight inch something like that square shaft um

00:48:07 you you might have a much bigger

00:48:12 sleeve but again you need to calculate but that was rather why i suggested one starts by deciding how big a piece you need to cut out of the corner then you box it in otherwise i don't

00:48:24 then you box it in otherwise i don't quite understand how you decide how large the boxing has to be um well this may not matter too much well i i think somebody panicking they told the group after they

00:48:36 panicking they told the group after they agreed to box it in um the question well how big is the boxing going to be i think was as small as possible

00:48:48 i think was as small as possible i suspect because of in possible obstructions within what is in fact a fairly narrow stair

00:48:58 all right thank you um i think we can deal with this point very briefly because it wasn't contested by mr dolan the boxing in was supposed to be two hours fire rated but

00:49:10 be two hours fire rated but when you considered the technical data sheet it didn't provide that fire rating did that's correct um i think we saw it had 88 minutes for uh resistance um

00:49:21 uh resistance um and we also know that the intumescent vents were not installed at least in so far as you could see the work

00:49:29 work in the stairs by the time of the fire is that correct that's correct um i think mr dolan said yesterday that it was the intention to cut those intumescents into the boxing inn at a later stage

00:49:42 into the boxing inn at a later stage um would that have been feasible to do it that way it would be feasible yes but have you seen any documentation which suggests that was what was planned no no now um

00:49:55 no no now um oversized holes we know that there were these oversized holes that were intentionally cut around the pipes between the stair and the lobby to allow ventilation through the boxing inn

00:50:08 and we know that that boxing in was not completed by the time of the fire on the 14th of june um is it right that it was completed on the stairwell side up to level 22 on the vertical

00:50:21 side up to level 22 on the vertical riser

00:50:23 riser i believe so yeah i've got photographs yes

00:50:27 yes i think you say in your report not it wasn't completed at level 23 but at the very top but it had gone right up vertically to 22. but on the lobby side the laterals had been boxed up

00:50:39 the laterals had been boxed up completely boxed up to level five but above that it was just that on the floors where gas was to be provided you just saw batons yes which had been put in um waiting for

00:50:51 yes which had been put in um waiting for the boxing but the boxing in wasn't actually

00:50:53 actually there is that correct that's correct and in your first report um you've drawn attention to the fact that

00:51:01 that it is possible in theory that smoke could have entered from the lobby side through those holes up the boxing in in the stairs and then potentially back through holes

00:51:13 and then potentially back through holes it was a breach of compartmentation yes you've drawn attention that is a possibility yes but you're not an expert in in smoke spread or

00:51:24 spread or you know how smoke might move so is it right that you've just merely drawn attention to this as a breach of compartmentation in your report yes um yes we've got the

00:51:35 in your report yes um yes we've got the photographs which shows the smoke staining yes i was going to just look at some of those so if we look at in your first report at rhx6012

00:51:45 rhx6012 page 165

00:51:49 we can see at level five two images of the stairwell yeah and there this is when after the fire when the boxing in has been taken off is

00:52:00 when the boxing in has been taken off is that correct that's correct

00:52:03 sorry the photograph at the top came from

00:52:06 from barbara lane's report right yes the photograph underneath was taken by a the metropolitan police photographer when i visited at the end of may yes

00:52:19 of may yes and as you can see the internal part of the the ducting is in pristine condition

00:52:27 condition yes so at the top we can just about see that the boxing in is still there at that point and then by the time the second photograph's taken it's been removed yes so you can see what's behind it and

00:52:38 yes so you can see what's behind it and then if we go and look at floor 9 on page 169

00:52:44 here we can see that there is smoke staining within that boxing in is that correct that's correct yeah and

00:52:52 yeah and you you can see particularly on the left hand side how you've got smoke staining on the riser side as well as the lateral yes

00:53:03 and if we go to floor 13 at page 173

00:53:11 you've also marked in the top photograph this was a photograph taken by dr lane

00:53:19 not long after the fire i believe and there

00:53:22 there there is a a missing panel at the end of the boxing in on the stair is that correct that's correct yes but is it right that we simply don't know when that missing panel might have fallen out whether it was not

00:53:34 might have fallen out whether it was not there because the work was unfinished or whether it had fallen out during the fire and removed we don't know that do we we don't know that that's correct yeah and is it right i think you also

00:53:45 yeah and is it right i think you also saw a missing panel from the boxing in on floor 21. yes another floor yes yes and if we look then at page 178 which is

00:53:56 and if we look then at page 178 which is floor 17

00:54:00 here we can see there's smoke staining along the lateral and slightly less smoke staining in in the vertical at that point

00:54:11 the vertical at that point yes yes and then at floor 18 if we go to page 179

00:54:20 this is a floor is this right where there were no flats too who required gas so there was just a vertical riser at this part that's correct and what we can see is there is some smoke staining at the

00:54:31 there is some smoke staining at the bottom but less smoke straining towards the top that's correct what you should refer to now in your opinion during the build should trio have

00:54:42 trio have done something about those oversized holes while the work was incomplete and that boxing in was not yet finished

00:54:55 i must admit that with hindsight the answer is yes but i don't think it would have been normal practice whilst the job was ongoing unless the

00:55:09 building owner or tmo as the responsible person for the building had pointed out to them yes we did see i i drew it to the attention of mr dolan yesterday that

00:55:20 attention of mr dolan yesterday that there was an email from cadent i believe drawing attention to the fact that there were these breaches of compartmentation during the works

00:55:31 compartmentation during the works and drawing that to trio's attention and the response came back from trio well yes

00:55:35 yes we know that the works are incomplete and i

00:55:38 and i think it was at a time when they'd been removed from sight due to the asbestos incident

00:55:43 incident yes in those circumstances where they had

00:55:46 had had it specifically drawn to their attention does it change your answer well if they were advised of it by their clients then then yes they should have done something it would have

00:55:57 done something it would have meant going back to the tml saying i know we've been chucked off site but there is this work which we feel should be done

00:56:06 be done yes and i'm sure that the tmo is a responsible and prudent operator would have agreed with that can you just explain that because why does it make a difference

00:56:17 it make a difference if the tmos simply draw trio's attention to something of which they were already perfectly well aware namely that the cadent i think

00:56:28 namely that the cadent i think like drew their attention to it well it doesn't matter who it was yes um why does it make a difference if someone drew their attention to the incomplete work of which they

00:56:39 to the incomplete work of which they were already themselves well aware it's question of

00:56:50 i i don't think the implications of the incomplete work would have been understood or fully understood so would i be right in understanding that in your view would make a

00:57:02 that in your view would make a difference if someone had said to them look i know that you

00:57:06 that you we both know the work's not finished but you should realize it might have these implications yes right but simply to say the work hasn't been done wouldn't really make much difference um

00:57:20 no it sounds as if they were being fobbed off

00:57:25 but um

00:57:32 to you you're then into client contractor relations and and who's in control yes i was just simply um trying to understand

00:57:43 simply um trying to understand uh to what extent you would criticize trio uh for having left these uh

00:57:55 left these uh gaps unsealed

00:57:58 at this at the time when they were still working

00:58:02 working on the installation i don't believe at that time uh the contractors generally were aware of the importance of

00:58:14 of the importance of uh not leaving those holes right until so i think what you're saying is you wouldn't particularly criticize them

00:58:25 wouldn't particularly criticize them for not having done it unless someone had not

00:58:30 had not only told them that the work hadn't been done which was self-evident yes but there was a reason for doing something about it yes in which case you would expect them to respond to that yes yes thank you that's i thought that's what you mean

00:58:43 that's i thought that's what you mean yes i think if we can we pull up that email it's at tri 60985 at page three

00:59:03 so this is an email if we just go back a page perhaps and just see who it's from it's from mary ryan at cadent to stephen johnson who we know was the design manager copying in

00:59:14 was the design manager copying in matthew dolan on the 21st of march 2017 and she says as we discussed on friday pat has visited grenfell this morning to review the works completed paying

00:59:25 review the works completed paying particular attention to the flats where holland gas have undertaken internal works and then if we go to the top of page three it says the agreement with the local authority was to install the new supply

00:59:36 authority was to install the new supply in the fire exit stairwell and box in to meet their evacuation requirements this has not been completed although there are ventilation holes throughout the stairwell which if a fire

00:59:47 throughout the stairwell which if a fire incident did occur would create a more unsafe situation now that's the email that's sent by cadent

00:59:56 cadent in your opinion would a reasonably competent

01:00:00 competent contractor at that point make sure that those

01:00:04 those ventilation holes were fire stopped while the work remained incomplete

01:00:11 yes yes

01:00:18 and and just to be absolutely clear on your evidence are you saying that before that's received you wouldn't have expected a reasonably competent

01:00:26 competent contractor like trio to have appreciated the need to fire stop those holes

01:00:33 holes while the work was incomplete i'm afraid i think that's the real world yes yes thank you now that the boxing in that was part of

01:00:47 now that the boxing in that was part of the second design which was boxing in not only in the lobbies but also in the stairwell in your view did that create

01:00:54 create problems in terms of future inspection and maintenance yes now we heard yesterday from mr dolan that

01:01:02 that um he said inspection could have been achieved

01:01:06 achieved either by the intermediate vents once they were installed or by cutting the boxing out for inspection so we know the intermediate well we're told that the intermediate vents might

01:01:18 told that the intermediate vents might have been on the stairs but i think at the lower levels he was saying you'd have to cut out the boxing is that

01:01:24 is that a satisfactory method in your view for allowing future inspection and maintenance of those pipes i would expect for future inspection maintenance

01:01:36 maintenance that inspection hatches would be cut into the boxing um if not then certainly there needed to be screws

01:01:45 be screws and screwed arrangements uh and in fact if you looked at the photograph of the boxing in on floor 5 you can see that there were screws which could be used to take off the

01:01:58 which could be used to take off the panel

01:01:58 panel to inspect but the norm is to fit an inspection panel which you can unclip or unscrew you can put a

01:02:09 unclip or unscrew you can put a gas detection instrument in you can put a

01:02:13 a duct camera in to look for any signs of any corrosion and that would be the norm yes now we know that there was a second design risk assessment that was

01:02:25 design risk assessment that was completed for this revised design that was in march 2017. if we can go to that at one two tri eight

01:02:39 this is dated the 24th of march 2017 and this document tells us that the the automated score still falls below the level

01:02:50 still falls below the level required to trigger a full design risk assessment but this time the manual override has been triggered we can see that at the bottom of the page

01:03:01 page can you see it says manual dra override needed

01:03:04 needed and the comment welded rider system and specific ventilation requirements and at page four we then can see the detailed design risk assessment that has been carried out um

01:03:18 that has been carried out um and we looked yesterday in particular at the mobs

01:03:22 the mobs multi-occupancy building specific hazards between lines 19 and 20 and some of the notes that were put in there now i'm not going to go through all of those notes

01:03:32 notes but um it was accepted yesterday by mr dolan that this was too generic and not specific enough um and can you just confirm that that's your view as you set out in your written

01:03:43 your view as you set out in your written report

01:03:45 report my view on it on this is totally inadequate yes not just generic and it's totally inadequate yes and in your first report as you've mentioned already

01:03:57 first report as you've mentioned already you've given a list of what you would have expected the designer to consider both in terms of the three topics we have here breach of complementation failure mode expansion

01:04:08 expansion thermal expansion and inadequate ventilation yes there's a lot more topics you would have expected within those three topics to be considered is that correct that's correct yes and you've also given a a list of

01:04:21 and you've also given a a list of other headings for multi-occupancy buildings

01:04:24 buildings like flooding corrosion means of escape yes that in your opinion should also have been considered is that right that's correct yes and so essentially for those reasons why you've

01:04:36 essentially for those reasons why you've just said that you your evidence is this was totally inadequate is that correct yes thank you

01:04:46 now um

01:04:49 i just want to look at what you say in conclusion about all of this uh design process and and this riser project at the end of your report so if we can go to page 210

01:05:03 your report so if we can go to page 210 rhx 6012 page 210.

01:05:16 at paragraph 446 you say you say this you say i am of the opinion that the ventilation of the riser and laterals had not been the subject of a sufficiently rigorous design process

01:05:28 sufficiently rigorous design process and that the design was not and would not on completion have been compliant with igem

01:05:32 with igem d5 edition two bs 8313 approved document b and the regulatory regime described above consequently i believe that the safest course of action open to cadent gas

01:05:43 course of action open to cadent gas limited once the option of running the replacement riser and laterals up the outside wall of the building had been ruled out by the tmo was to refuse to replace the pipeline

01:05:54 refuse to replace the pipeline on the grounds of being then we go over the page

01:06:06 on the grounds of being unable to comply with current legislation and standards and to compensate the residents accordingly so and and do i take it that that conclusion hasn't changed

01:06:17 conclusion hasn't changed that conclusion has not changed yes

01:06:28 and it's right isn't it that it's your view that the gas transporter could have refused to connect these properties to gas had they wanted to had that been their conclusion about the

01:06:40 had that been their conclusion about the rises i i believe so i i believe um subsection nine of section 10 yes of the gas act gives that um the gas transporter the

01:06:54 gives that um the gas transporter the uh option of uh refusing to make supply available yes and is that provision well known and used in the gas industry

01:07:05 used in the gas industry i don't believe so do you consider in your opinion that the gas industry ought to consider the option of refusing to supply gas on the basis of safety

01:07:15 of safety more often

01:07:19 quite possibly i i think they should be much more aware of that whilst i'm sure that he could end up in a few court cases it's something that they at the moment that

01:07:30 something that they at the moment that has been for years a culture that if a gas supply is cut off for an escape it will be replaced come hooker by crook yes even if that means

01:07:44 yes even if that means non-compliance with current standards and that

01:07:48 and that culture possibly needs to change yes thank you

01:07:52 thank you mr chairman um there's one remaining fairly sizable topic left which is recommendation but i'd i'd like to deal with that in one go if i could

01:08:03 with that in one go if i could could we take the afternoon break now and then

01:08:07 and then resume again at an appropriate time yes well we can do that um i'm sure it is quite a sizeable topic but you're not going to have any difficulty oh no sorry i'm not signaling that i've

01:08:19 oh no sorry i'm not signaling that i've got a problem finishing it's just it seems no no to start the topic and just do five minutes and then break it quite well we'll break now and we'll take our afternoon break a little earlier than usual miss hancock so we'll

01:08:30 earlier than usual miss hancock so we'll stop now we'll come back at 25 past three and then move on to the next topic all right

01:08:36 all right thank you very much and please don't talk to anyone about your evidence you probably won't have much of a chance to do it all right thank you would you like to go to the usher thank you

01:08:52 thank you right twenty-five past three though scringe thank you

01:26:34 yes would you ask mr hancocks to come back in please

01:26:53 right yes ready to keep going cox thank you very much yes it's great yes thank you um so now on to the topic of recommendations so you make at the end of your report and in the light of all the evidence you've considered and

01:27:04 all the evidence you've considered and the conclusions you've reached you have made a number of recommendations uh for the panel to consider

01:27:11 consider and the panel's decided that it would like to hear from you on that today because

01:27:14 because gas is is quite a self-contained topic so yes we have time to do that now now the first recommendation is about a replacement decommissioning riser program in your

01:27:27 decommissioning riser program in your evidence you've identified a number of problems

01:27:30 problems with old residential supply one in particular the lack of sleeving of rises and pipes being run through unventilated voids

01:27:39 voids and um we've understood from your evidence that those design features were permitted in buildings constructed before the 1st of december 1972 is that correct that's correct yes now let's just look at the key

01:27:50 let's just look at the key recommendations you make about this in your first report so if we go to rhx6012 at page 220. and we look at paragraph um four six

01:28:03 and we look at paragraph um four six eight and four six nine i want to look at you you tell us at four six eight many high and medium rise blocks of flats were designed and constructed prior to the effective introduction

01:28:14 effective introduction of the gas safety regulations 1972 which required pipes to be sleeved through walls and floors and not to be placed in unventilated voids to my knowledge there are a significant number of blocks of flats in london

01:28:26 number of blocks of flats in london scotland central belt and other cities in the united kingdom of similar vintage and with the same sleeving and ventilation issues as exhibited by residential gas supply

01:28:37 exhibited by residential gas supply number one and then you say at 469. therefore i believe the inquiry should recommend the gas transporters and by

01:28:45 and by implication other interested parties such as the hsc off gem and local authorities and housing associations with private gas networks have a replacement decommissioning program for internal

01:28:57 decommissioning program for internal risers and laterals that are not compliant with the gas safety regulations from 1972. so that's your that's your recommendation now i just want to clarify something about

01:29:08 clarify something about that last sentence at this stage where you note

01:29:12 you note that it would be buildings that are not compliant with the gas safety regulations 1972. um are you referring specifically to buildings which by virtue of their age

01:29:24 buildings which by virtue of their age did not have to comply with what we would now consider basic safety features such as sleeving and ventilation that were contained in those regulations

01:29:36 i am particularly aiming at that should be

01:29:39 be aimed at buildings which do not have sleeving or which have um pipes going through unventilated voids

01:29:51 pipes going through unventilated voids the other the two i think principal risk factors

01:29:55 factors of pipes of that age to which you would then add on the possible effect of long-term corrosion and that we also saw it on residential

01:30:06 that we also saw it on residential supply number one yes um yes and just to be clear you're not saying is this right that we should replace or decommission pipes in modern compliant buildings just

01:30:18 pipes in modern compliant buildings just because they don't meet all the prescriptive requirements of those 1972 regulations no it's

01:30:26 basically i i think effectively if you've got risers which do not have sleeves which are concreted into the floors

01:30:37 the floors and or have got unventilated voids something should be done about them yes um and can you confirm that the hse itself has been focusing on gas supply

01:30:48 itself has been focusing on gas supply to tall buildings recently in terms of its work yes and can you confirm that that work includes in may 2018 the hse started an inspection program

01:30:59 inspection program on the arrangements for managing the integrity of pipes in buildings over six floors

01:31:05 floors is that correct that's correct and to do that they issued something called a topic

01:31:09 topic pack is that right that's correct we'll come to that in a moment and they reported back on this in february 2020 is that correct that's correct now the topic pack and the report those

01:31:21 now the topic pack and the report those are public documents is that right yes and in your view has the hse investigation been extensive into this i've been reasonably inspect uh recently

01:31:34 i've been reasonably inspect uh recently extensive yes and is the report that's been provided by the hsc i think you say in your supplemental report that it's an authoritative and reliable report yes now if we go to the topic pack at

01:31:47 yes now if we go to the topic pack at rhx6015

01:31:51 we can see here it is it's a topic inspection pack and it's dated may 2018. and was this the document that was issued by the hse to inform

01:32:03 issued by the hse to inform how their inspection program would work yes

01:32:07 yes and if we go to page seven at the bottom of the page we see under 7.2 benchmark we can see it says this it says the

01:32:18 we can see it says this it says the benchmark standard for pipelines is defined within the pipeline safety regulations 1996 and then it quotes regulation 13 about maintenance dictates that the operator

01:32:29 maintenance dictates that the operator shall ensure that a pipeline is maintained in an efficient state in efficient working order and in good repair and then the hsc is added so that in all cases there is a nil

01:32:40 in all cases there is a nil negligible chance of a significant injury occurring now do you take that last sentence and and the reference to nil or negligible chance of significant injury

01:32:52 chance of significant injury to be the standard at which the hsc expects that all gas transporters will keep their service pipeline safe too yes

01:33:05 now is it your view that a proactive program to replace older steel risers that fall into the category you've just described is required in order to achieve that

01:33:16 is required in order to achieve that standard yes now in your supplementary report you give some more detail on on different replacement philosophies that are known about in the gas industry i

01:33:27 about in the gas industry i different approaches to addressing gas work um you refer to something called the reactive philosophy um is that where replacement

01:33:41 philosophy um is that where replacement is only considered where the riser has failed completely usually yes basically as a result of a public reported escape or as in the case of grenfell riser two that

01:33:52 that where their inspection finds a leak yes and they have to cut off the riser yes and then you refer to something called predicted replacement and is that

01:34:03 predicted replacement and is that understood to be where data analysis is used to predict the imminent failure of a riser such that action is taken before an escape occurs yes so you've got to have data available to

01:34:17 so you've got to have data available to you to be able to make that prediction is that correct that is correct and then you distinguish between those things and something called preventative replacement and is that where there is a systematic

01:34:28 and is that where there is a systematic program of replacing rises and laterals with

01:34:32 with known risk factors such as pipes being concreted into floors or without inadequate ventilation yes and

01:34:40 and and what you're saying is you're recommending a systematic program of replacement for those with known risk factors already is that correct yes and just to be clear is it is it

01:34:53 yes and just to be clear is it is it your opinion that a serious gas incident is likely to occur if a wholly reactive philosophy is continued to be employed yes i believe the probability of serious

01:35:04 yes i believe the probability of serious gas incident is greater in that's those circumstances yes and have you are you able to help us as to how likely you think it is

01:35:15 to how likely you think it is i mean this is something that is no the the very you know a significant possibility

01:35:24 there's a paucity of data including

01:35:32 likelihood of failure of riser systems and likelihood of failure of rightly rising systems leading to an incident

01:35:43 incident and i suppose the industry's in the situation where it can either say we haven't got enough data do nothing

01:35:51 nothing or we recognize these factors and we do something about it um

01:36:00 yeah but my question was really a response to your previous answers you were invited by ms grange to

01:36:08 grange to confirm that you believed that there was a

01:36:11 a probability of a serious gas incident i'm sorry yeah and i wanted to get some sense of how serious this problem

01:36:22 this problem is and and whether you think that there's very likely to be a serious incident or just a a fairly remote possibility of an incident or where on the scale between them

01:36:32 them it's a less remote problem uh probabilities and those it's likelihood of a serious incident fortunately is going to be low but if you only have a reactive policy

01:36:45 but if you only have a reactive policy it is more likely that there will be of course a serious incident with just a pure reactive

01:36:53 reactive policy right thank you yes now you say that a predicted replacement strategy

01:37:00 strategy relies on data analysis now is it realistic that a gas transporter will be able to get sufficient accurate data to inform that sort of

01:37:11 accurate data to inform that sort of replacement strategy at this time

01:37:16 as the industry's currently organized probably not i think the there needs to be a coordinated national approach that takes in all of the gas transporters

01:37:29 takes in all of the gas transporters and a pooling of data

01:37:33 i think that would be essential um possibly to the hsa acting as referee um but essentially

01:37:44 um but essentially to get the data there's got to be access as in access to the buildings yes access to the building to the different parts of the building yes so i think what you're saying is if you try to do

01:37:55 what you're saying is if you try to do some kind of predictive replacement program

01:38:00 program the big challenge is obtaining proper data

01:38:03 data about the condition of pipe work within many of these buildings yes is that correct yes and you've said the main problem is access um

01:38:14 um are you concerned that just like at grenfell these older risers are likely to be built going from flat to flat in many buildings

01:38:22 buildings there'll be a significant number of where that is the case yes yes that's a common feature i believe of buildings of that vintage yes so if you were trying to

01:38:33 vintage yes so if you were trying to get better data on these buildings that requires you to be able to get access to an awful lot of flats to assess

01:38:41 assess that pipeline is that correct it does and

01:38:44 and access for inspection also depends on people being at home at the time and also willing to provide the access is that correct um is there also a problem

01:38:55 um is there also a problem in your view about visibility of pipes because of their location in buildings in terms of being deep in buildings or deep in concrete within buildings

01:39:08 within buildings some of the very old uh systems will actually be embedded in the fabric of the building you know within the wall um as well as in just going through

01:39:21 as well as in just going through floors and walls um but

01:39:32 you this is where you want looking at

01:39:36 gas systems which are 50 plus years old yes um and some of them will even be pre-war

01:39:45 pre-war yes and does it follow from what you've said that any predictive replacement strategy would be difficult to achieve to reliably inform a safe replacement

01:39:57 to reliably inform a safe replacement strategy is that what you're saying i am i have i am skeptical that

01:40:07 sufficient data or will be available or that the any sampling will be representative of of the riser we we

01:40:18 representative of of the riser we we heard yesterday that cadent actually did pretty well to get access to 40 of the um properties in in grenfell um

01:40:31 in grenfell um and that's a much higher figure than i have

01:40:34 have heard as a general generalization from from others so

01:40:41 this the whole access issue getting data to predict

01:40:49 predict whether when if you like the other risers of grenfell would have failed

01:40:55 failed um i think the jury's out on that right on reading the hsa report right yes now if we go to

01:41:07 hsa report right yes now if we go to your supplementary report page 12 that's rhx6020 at page 12. you you tell us at the bullet point at the

01:41:18 you tell us at the bullet point at the bottom just before paragraph 23 you say a preventative replacement program will involve the replacement of rises before imminent failure is likely on the other hand a preventative

01:41:30 on the other hand a preventative replacement program targeting those rises with known risk factors should reduce the risk of a serious gas incident occurring and will not be overly hampered by the absence of data from difficult to

01:41:42 by the absence of data from difficult to access locations so is it right to understand that any preventative program that you're proposing

01:41:50 proposing would identify certain risk factors and then require buildings at highest risk to be replaced first yes so you're not saying you take all the buildings

01:42:02 buildings that were pre-1972 that appear to have no sleeving and no ventilation and you just blank it replace all those risers are you saying that any program

01:42:14 risers are you saying that any program would need to prioritize those that you should be approaching i think

01:42:21 think certain issues your starting point that would be your basic data there may be buildings you just cannot get in or you can only get into one or two locations

01:42:32 and my concern about a predictive approach

01:42:36 approach is that if you can only get into one or two flats or one or two locations it may not be sufficient to form a

01:42:44 form a valley judgment

01:42:47 so it's almost a mix of trying to prioritize what you're doing but

01:42:57 i i am concerned that at the moment was it cadence saying that they are i think they said the other day 80

01:43:09 i think they said the other day 80 percent of their current replacement is reactive yes 20 of it is what they call proactive

01:43:18 those figures concern me that is basically a reactive program yes and when you talk about known risk factors

01:43:27 factors that put them in put your buildings into this initial pool of buildings of concern just to be clear are we talking about buildings with unventilated voids and no sleeving

01:43:39 unventilated voids and no sleeving primarily yes are there any other risk factors

01:43:43 factors that would be easy to identify that you think ought to qualify them for this kind of program yes three inch and four inch or even six inch screwed steel so the screw it screwed joints bigger

01:43:55 so the screw it screwed joints bigger than 2 inch yes no longer allowed not just in this country but in europe for gas work basically because of their the probability of leakage from them

01:44:06 the probability of leakage from them their failure rates yes and how would you understand that buildings with those risk factors be identified combination of continuing surveys but

01:44:19 combination of continuing surveys but also

01:44:20 also liaison with building owners yes so there'd have to be a proactive engagement with building oh definitely yes to identify this pool of buildings is that right yes i believe can i just

01:44:32 is that right yes i believe can i just intervene again there because i'm going to hold these questions back for the end of this part of the examination but since you've raised the question of getting in touch with building owners is this a problem

01:44:44 with building owners is this a problem which in your view these problems the two that you've specifically identified are they limited to buildings in multiple occupation

01:44:56 multiple occupation there is a significant problem in parts of the country of finding out who the building owner is in the first place

01:45:07 and

01:45:11 the problem is that many building owners and residents consider or certainly give the impression of considering

01:45:22 impression of considering an inspection or of the gas system as an unwanted intrusion and i asked the question

01:45:29 question because um there are some buildings in solo occupation which have parts which have solid floors probably concrete screeds

01:45:42 probably concrete screeds uh particularly in the areas of kitchens where there may be gas boilers or gas cookers

01:45:50 cookers and potentially unsleeved connections should we be having them in mind as well when we make recommendations for replacing

01:46:01 replacing unsleeved pipework

01:46:06 i assume you're talking about the installation pipe work for the industrial dwelling this is the pipe work before it reaches the meter and therefore is the responsibility of

01:46:18 and therefore is the responsibility of the gas transporter if i've understood it correctly yes um then that is something that um

01:46:31 that is something that um i would have thought would be dealt with under the standard replacement i'm talking for individual properties then that i'd have thought would have

01:46:42 then that i'd have thought would have been dealt with as part of the iron mains replacement program so um you think we can safely ignore uh buildings in seoul or single occupation

01:46:55 buildings in seoul or single occupation um

01:46:59 i i think that they're down the list of what you can say maybe but i'm just really want to know whether the we're looking at all these things into the prism of grenfell tower of course we

01:47:10 the prism of grenfell tower of course we are

01:47:10 are yes but nonetheless if we're being invited to make recommendations which are related to the existing gas infrastructure there are many

01:47:21 gas infrastructure there are many buildings

01:47:22 buildings which are much older than grenfell tower which will have gas yes possibly of some antiquity and which may have solid floors therefore concrete or similar types of

01:47:34 therefore concrete or similar types of material

01:47:36 material through which or near which the gas pipes are running which raises the problem of corrosion or the heightened problem of corrosion should we ignore those or should we take this into consideration

01:47:48 this into consideration i think the industry must not forget it um

01:47:52 um and certainly when i was active in in british gas there was a service replacement program

01:48:02 to what extent that a lot of services were replaced in advance of any mains replacement

01:48:13 so

01:48:17 it's

01:48:20 certainly um

01:48:24 should be on the list of assets to be considered for replacement thank you and the other thing is this we

01:48:36 thank you and the other thing is this we again for obvious reasons we're looking at this principally through the prism of the high rise built at the moment high-rise buildings are conventionally identified as being

01:48:47 are conventionally identified as being buildings with a story over 18 meters in height

01:48:50 height i take it that these problems are not limited to buildings of that height true yes i i'd point out that we elsewhere in in the report about

01:49:02 that we elsewhere in in the report about recommendations relating to what michael medium will uh rise but these problems in a sense are of a generic nature yes and and so if we're thinking about

01:49:13 yes and and so if we're thinking about making recommendations we would be unwise to limit them to high-rise buildings yes yeah thank you yes yes ms great sorry thank you very much thank you within any proactive program that might

01:49:24 within any proactive program that might be recommended is there still a place for gas transporters to be identifying and assessing risks in the way they are at the moment as described by cadent

01:49:35 described by cadent and thereby identifying the most dangerous building for earliest replacement uh there's still there's a place for it yes

01:49:43 yes um but uh

01:49:49 it's if they can identify the risk and you're doubtful that they they can because of the access problems yes yes now you've mentioned it just briefly

01:50:01 yes now you've mentioned it just briefly uh already in your answer to the chairman but you you go

01:50:05 you go into some detail in your supplemental report in drawing on your experiences with something called the iron mains replacement program yes um now can you just describe very

01:50:17 yes um now can you just describe very briefly what was the problem with the iron mains well basically the work that was done in the early days of british gas to the early 70s

01:50:30 identified that the majority of incidents involving casualties and explosions

01:50:41 casualties and explosions came from small that's three inch and four inch cast iron pipes particularly where they were

01:50:52 pipes particularly where they were in streets where the the sealed surface all the way to the property or where the property had sellers

01:51:04 sellers so any and there was a risk with the smaller diameter mains having less beam strength so any ground movement they would break yes so you get plenty of gas coming out

01:51:17 yes so you get plenty of gas coming out of the gas escape yes getting into a property source of ignition

01:51:24 ignition explosion yes and is it right that initially those were being dealt with by a wholly reactive policy so only being replaced when they were falling apart yes

01:51:35 falling apart yes and replacement being a last resort yes and was that approach challenged there were engineers at the time who expressed their views quite forcibly

01:51:45 forcibly yes and did that lead to a report by somebody called doctor or professor king is that correct well the incidence of um

01:51:57 well the incidence of um escapes or explosions generated by explosions over the christmas period of 76

01:52:05 76 to 77

01:52:09 so anthony wedgwood ben was the minister at the time yes agreed with the then chairman of british gas that there should be a report produced an analysis and that

01:52:20 an analysis and that that happened and the out of that report came a major

01:52:32 risk program to replace the high risk mains which basically the three inch and four inch pipes yes in certain locations and that was a

01:52:44 yes in certain locations and that was a proactive

01:52:45 proactive mains replacement program oh yes correct yes and just so we're clear you're not saying that the problem with the iron mains is exactly the same as the problem we have with these risers in these

01:52:57 we have with these risers in these buildings you've drawn attention to but what you're saying is there's an analogy here in terms of there was a move from a reactive strategy to a proactive strategy is that that's correct i could see the

01:53:08 that's correct i could see the similarities with what was happening incidents and the reaction to the incident

01:53:16 incident yes and was a program put in place to prioritize or target the mains most at risk

01:53:21 risk first yes we went after three inch cast iron mains in what we called hazard a

01:53:29 a areas which is where the

01:53:34 either the front of the house was actually butted onto the footpath or would be say a one or two meter wide front garden that had been concreted over

01:53:46 concreted over yes and we did those yes and and you mentioned in your supplementary report that following the decision to go with this proactive program there was then a rapid

01:53:57 proactive program there was then a rapid increase in pipeline teams with supervisory and technical staff um with the ability to go and replace these mains is that correct that's correct

01:54:07 correct um and that work is still being completed is that right yes there is still an iron mains replacement program yes and there is in fact a regulation in the 1996 pipeline safety regulation which

01:54:18 1996 pipeline safety regulation which deals with how the hse will work with transporters on their programs to replace iron pipelines correct yes

01:54:31 now if we just go back to the topic pack for a moment at um so rhx 6015 at page 10.

01:54:47 we can see at the bottom of the page at the second row from the bottom this is in a table of questions that the hsc was asking of of relevant buildings and it the

01:54:59 of relevant buildings and it the question is is a clear risk-based prioritization system in place in relation to inspection maintenance and condition replacement now there's no doubt is there that the hsc does expect

01:55:11 hsc does expect gas transporters already to have a risk-based system in place for assessing their gas

01:55:16 their gas assets oh yes yes and the inquiry has seen evidence that grenfell tower was surveyed in 2016. and can we agree that that survey did

01:55:28 and can we agree that that survey did consider the risk of the existing residential supply one and did make a decision to replace the whole of the riser at some point so a survey was done here a problem was

01:55:40 a survey was done here a problem was detected

01:55:42 detected and the upshot was that eventually that whole riser was going to be replaced through the new riser can we agree that that that action did happen

01:55:51 happen yes was that not an example of a survey survey process working to deal with the problem of these older potentially unsafe risers

01:56:04 um

01:56:08 i think if they'd eventually got into the flat where severe corrosion had been seen i would say yes

01:56:21 it's partly on the way there yes yes so i think what you're drawing attention to is it was then eight and a half months to the fire and still nothing had been done

01:56:32 the fire and still nothing had been done in terms of their more detailed corrosion survey work yes yes so um why is that in principle not a sufficient way to deal with the problems

01:56:43 sufficient way to deal with the problems with these old steel risers

01:56:51 the impression i have is that just possibly certainly in london carried into swamped

01:57:02 my sheer number of properties that they're looking at so does it follow that you're doubtful that the problems will be adequately addressed

01:57:13 be adequately addressed by way of their current processes yes i i am doubtful it might be said that some gas transporters already account for the problems of access in their surveys for example if they can't

01:57:25 their surveys for example if they can't see a pipeline they give the building a higher score and choose to assess it more frequently until there is remedial action if a gas transporter already had that approach

01:57:38 transporter already had that approach why would there be a need for a preventative replacement program i'll keep going back year after year to try to get in to inspect and do nothing

01:57:51 because they can't get in yes [Music]

01:57:54 [Music] it's you've got to break that loop of keep going back year after year and trying to get in to collect the data yes

01:58:05 trying to get in to collect the data yes now in general and i think you confirm it in your supplemental statement but i just want you to confirm it now can you confirm that you've read mr harrison's it's his third inquiry statement

01:58:16 statement it's his fifth statement in time from dated this year i think march this year and considered the reasons why he says a preventative replacement strategy is not necessary given other processes

01:58:29 is not necessary given other processes and procedures that cadent has in place

01:58:33 i have read his his statement uh i i note his reference to resources and costs and

01:58:40 costs and as opposed to safety um

01:58:46 and i do not have faith that they're getting the data necessary for a risk-based predicted

01:59:01 for a risk-based predicted replacement system yes so can you confirm has your view on this recommendation changed at all as a result of reading his evidence my view hasn't changed no yes

01:59:15 if we go to the hse report of february 2020 this is rhx 6014.

01:59:31 rhx 6014. so here is the report that the health and safety health and safety executive published and we go on the third page

01:59:42 sorry here's the front page of the report and it's headed gas supplies in high-rise multi-occupancy buildings inspection findings at page six of this report if we go page six of this

01:59:53 of this report if we go page six of this clip we get the executive summary and if we just look at paragraph 2.5 we can see it says a lack of quality records in relation to the design

02:00:05 records in relation to the design installation inspection and maintenance of gas networks

02:00:09 networks supplying high-rise dwellings is a common observation and restricts the operator's ability to provide a robust demonstration of network integrity given the practical difficulties involved in providing assurance of the

02:00:21 involved in providing assurance of the condition of the network further work needs to be undertaken by the industry on the basis by which risk-based decisions on inspection frequency and replacement are made now does that tell us that the

02:00:35 are made now does that tell us that the hsc considers that there's more work to do

02:00:38 do before they are satisfied that grass transporters have a sufficient surveying and reaction strategy

02:00:46 strategy i believe so yes and is it true that the hsc

02:00:50 hsc is is still currently investigating this issue as far as i'm aware yes if there's a problem

02:00:56 a problem with the risk-based systems that gas transporters are using wouldn't the hse be the better body to decide on the basis of the evidence it gathers

02:01:05 gathers what to do about gas transporters whose risk-based systems are inadequate um

02:01:14 a strong argument can be made that they are the appropriate body yes that doesn't stop me having an opinion yes now it's been said

02:01:25 yes now it's been said um and and you've already alluded to that mr harrison makes these points he makes a number of points in his statement but he also makes these points that your proposal will cost a great deal of money

02:01:36 deal of money that it will result in timing and workforce issues which will drive up cost

02:01:41 cost for customers that it will be disruptive to a lot of customers and it's also been said that it's not proportionate um what's your response to those

02:01:54 um what's your response to those concerns about it being disproportionate to the size of the problem prove it my answer would be to ask him to prove it

02:02:05 to prove it and what do you mean by that when you say prove it

02:02:12 i think there is a problem

02:02:16 and i believe it needs to be tackled

02:02:20 and to try to dismiss the concerns by saying all disproportionate i'm afraid is

02:02:27 afraid is um

02:02:31 i i i don't accept straight off i i think he needs to demonstrate that like proportionality is what the risks are

02:02:41 are for that they need data yes um and in the light of what we've seen at grenfell um

02:02:53 of what we've seen at grenfell um there's um i think some work has got to be done yes he has said that a conservative estimate of um dealing with this problem as you

02:03:06 of um dealing with this problem as you propose would be somewhere in the region of 170 million pounds um he's estimated that something like

02:03:13 like 8 300 rises might fall within the definition your definition of those that would need addressing and he estimates approximately 20 000 pounds per riser which is how he gets to

02:03:25 pounds per riser which is how he gets to around 170 million um

02:03:32 but do i take it from your previous answer that that doesn't affect the fact that you still think that that needs doing with regardless of whether the costs might be in that in that

02:03:43 in that in that order i i see that there is a population out there that's getting older and older the population of assets that get

02:03:54 the population of assets that get getting older and older and with that if there is any deterioration through corrosion etc

02:04:06 there will need to be a a program to deal with it otherwise they're going to get swamped with incidents and there could well be

02:04:17 with incidents and there could well be a serious gas explosion etc yes and you've said in your report that you wouldn't be able to give any indication as to the time scale in which this kind

02:04:29 as to the time scale in which this kind of proactive work would need to be undertaken um can you explain why it's difficult to predict time scale well again it's down to the data

02:04:40 data just how many buildings are out there what state they are in what is their predicted life at one time there was talking the industry

02:04:51 industry of a steel system into a building of having a

02:04:55 having a a design life of 25 years but we're well beyond that in respect of high-rise buildings at other times there's a discussion in terms of

02:05:06 there's a discussion in terms of the length of time that you'd expect a gas main to be in a road and i think you're talking 80 years well that takes you to what um 1919

02:05:18 to what um 1919 1940 um

02:05:22 1940 um so anything that's pre-war would be covered

02:05:25 covered there yes um so

02:05:30 i'm very conscious that we've been living on

02:05:35 living on the industry has expanded considerably over the years

02:05:41 and assets are getting older and if they've got issues potentially on corrosion particularly then

02:05:53 they will come home to roost yes

02:05:57 now you mentioned in your supplementary report that currently there is a possibility of gas supply converting to 100 hydrogen is that correct that's correct so that would be a different fuel replacing natural gas yes

02:06:10 replacing natural gas yes um now 100 hydrogen is not yet approved for use in multi-occupancy buildings over five floors is it no well the current thinking no evidence that

02:06:21 that it can be done safely yes right um so is it right that even if that change happens it will still be a number of years before there's full conversion yes yes and does it follow that in your

02:06:33 yes yes and does it follow that in your view there's still a place for a recommendation about a proactive strategy

02:06:38 strategy for buildings with the unsafe features you've identified yes the we don't know the effect of hydrogen

02:06:49 hydrogen particularly particularly for multi-occupancy buildings um we don't know whether the domestic consumers will able will be able to be

02:07:00 consumers will able will be able to be supplied with hydrogen because the calorific value is about a third of that and natural gas and so you've got um capacity issues on the gas networks

02:07:12 the gas networks um there are a lot of unknowns with hydrogen there's a possible as i say there's a possibility i was flagging it up there and it's made

02:07:23 i was flagging it up there and it's made as a possible as an unknown yes um that may well be into a situation in in 10 15 years time

02:07:36 where there's a decommissioning program uh well because of hydrogen yes i don't know yes

02:07:46 know yes i understand now um pivs now an accessibility of pips your second recommendation relates to these and if we can look at your report your first report at rhx

02:07:59 your report your first report at rhx 6012 220

02:08:04 paragraph 472 you you're referring in the previous paragraphs to the problem of piv valve's boxes being lost and we've already discussed that today i'm not

02:08:15 already discussed that today i'm not going to go back over that and you tell us at 471 that the current inspection practice is to check the accessibility of the piv at the same time as the rest of the gas infrastructure for the block of flats being inspected and this can be

02:08:27 of flats being inspected and this can be as infrequent as 10 years which in your view is too long yes and you tell us that you're aware that under the gas safety management regulations each

02:08:38 gas safety management regulations each gas transporter is required to undertake a thorough review of its gas safety case every three years and is required to submit a report of that review to the hse and you say as you believe that

02:08:50 hse and you say as you believe that three years is a suitable frequency for checking the accessibility of pivs and the submission of three yearly reports to the hse provides a suitable opportunity for a progress report to be made

02:09:01 made you believe that the inquiry should recommend that the hse mandate each gas transporter to carry out a three yearly piv accessibility inspection program and progress

02:09:12 progress on that inspection program and progress on that inspection program should be reported upon in the three yearly report so that's your clear recommendation

02:09:27 and just to clarify you mean that piv accessibility is something that should be included in the gas transporter's safety case and then in the three yearly updates to the agency it could be a

02:09:39 the agency it could be a very easily a short section in the in the report he focuses the mind yes of the management on yes progress now in terms of of time scale

02:09:50 progress now in terms of of time scale you say that reporting on this every three years is is about right in your judgment can you just explain why you say that um

02:10:02 three years

02:10:06 you can argue a fair bit can happen in three years but you've got a three-year reporting progress already process already there so in that sense bolting the reporting

02:10:18 in that sense bolting the reporting process onto the

02:10:22 the safety case reporting report the pips can be lost because of resurfacing work um

02:10:37 resurfacing work um other utilities doing work and reinstating their trenches and in the reinstatement doing away with the

02:10:45 the valve box

02:10:49 they can be lost because of landscaping work done by building owners and

02:11:01 the if you're going to check on the accessibility of pipeline appears as i say if you've got a record of the pivot in the first place

02:11:13 of the pivot in the first place then it's actually a very short duration job to actually check its accessibility yes because as you explained earlier you don't actually have to activate the

02:11:24 don't actually have to activate the valve

02:11:24 valve in fact you you wouldn't recommend it i don't recommend that that's right you literally just have to check that the chamber is there and that it's clear yeah correct yes so you don't think this is particularly onerous in terms of what

02:11:35 is particularly onerous in terms of what it's imposing it's something that could be given to a an individual with a van and a small set of small tools and a list and plans and he would

02:11:47 and a list and plans and he would literally go from site to site to site it's not a high skill job and it you can do far more sites yes than that than if

02:11:57 than if that involved with the high right building surveys yes now tayden has suggested that the draft building safety bill

02:12:08 building safety bill that we know is been presented to parliament um at the moment would give an opportunity to make a different identical identifiable party i.e the role of

02:12:21 identifiable party i.e the role of accountable person responsible for ensuring that the pivs are not covered up now do you accept that that would be an

02:12:33 now do you accept that that would be an appropriate way of addressing the problem of lost pivs it would be a way an action that would assist in some circumstances

02:12:46 would assist in some circumstances yes i would not expect the accountable person to have any involvement where the pipeline isolation valve is actually located in the public highway

02:12:57 located in the public highway yes because they would have no jurisdiction to be able to do anything about that that's correct yeah i would not expect that person or organization

02:13:09 expect that person or organization to proactively look after the pipeline isolation valve box it's not something they're involved

02:13:21 box it's not something they're involved with they have plenty of other things to be getting on with they're not gas specialists and so not necessarily know the importance of them and the responsibility for those wells

02:13:32 responsibility for those wells rests with the the gas transporter yes so i would argue that it's part and parcel of the need for a proper dialogue and a proper relationship between the gas transporter and the

02:13:45 between the gas transporter and the responsible person for the building stroke accountable person yes so is it fair to say that you think there might be a role for the accountable person in terms of them being the nominated

02:13:56 in terms of them being the nominated point of contact for the gas transporter and assisting with challenges over accessing the building yes definitely but you still are of the view that the ultimate responsibility

02:14:07 view that the ultimate responsibility for checking the pivs and making sure they're accessible should remain with the gas transporter yes is that correct yes and

02:14:19 yes and this problem of lost pivs does that only apply to high the high-risk buildings that might be covered by the draft building safety bill no it's it

02:14:29 it it's all commercial buildings and

02:14:37 i feel like blocks of flats with where there's more than two um consumers yes so a lot of all the low rise and medium rise

02:14:48 medium rise as well as the high rise if this building's got to pipe my nice gas supply and a pipeline isolation valve

02:14:57 valve that would come into it as well does it not apply to ordinary domestic premises they don't have a pipeline isolation valve they don't have one at all

02:15:08 valve they don't have one at all um do you think it would be sensible for the accountable person and possibly also the responsible person under the rro the 2005 regulatory reform fire safety order

02:15:19 order do you think it would be sensible for them not to have to have a duty not to cover up pivs in any event and separate from your recommendation

02:15:30 and separate from your recommendation um one can argue that if you could and but i would ask the question is it enforceable

02:15:38 um i i've got my doubts right yes um

02:15:45 yes um the third recommendation that you make is about the standard for excess flow valves and thermal cut-off devices we took talked earlier about excess flow valves and thermal cut off devices

02:15:59 and those are devices that can be fitted to pipelines that will cut off the gas supply if an open end starts discharging gas is that correct that's correct and this follows your observation that

02:16:10 and this follows your observation that the flats continued to burn until isolation because of some open ends at the meters is that correct yes now is it right that there's no requirement to specify these excess flow valves or

02:16:23 to specify these excess flow valves or thermal cut-off devices at the moment no that that's specified at least within igm g5 but the actual specification to which they

02:16:35 specification to which they those fittings comply are actually german

02:16:39 german specifications

02:16:42 one could argue that we ought to have a a british standard or a gas industry standard for those those fittings yes and we can

02:16:54 for those those fittings yes and we can see

02:16:55 see that recommendation if we go to your first report rhx 6012 at page 221

02:17:05 yes this is where you're dealing with that standard and if we just read 476 and 477 you say currently there's no british or industry or gas industry standard for excess flow valves and

02:17:16 standard for excess flow valves and thermal cut-off devices you say there's german standards for both fittings and there's an american standard for excess flow valves and you believe that the inquiry should recommend the gas industry associated manufacturers and british standards

02:17:28 manufacturers and british standards institution produces standards suitable for use in the united kingdom is that correct that's right yes thank you and then finally the fire resistance of um

02:17:40 finally the fire resistance of um domestic meter installation components that's your final recommendation and we can see that below on that same page and this follows from when we were looking

02:17:51 this follows from when we were looking at that photograph before of the the resistance of each of the components of the meters what you say is that there's no mention of fire resistance of other components

02:18:04 of fire resistance of other components making up a meter installation ie pliable

02:18:08 pliable go over the page pliable connectors yes i apply pliable connectors and the regulators and you think there's a disconnect with

02:18:20 and you think there's a disconnect with the fire resistance requirements in appendix a of approved document b because other parts of the meter are required to have fire resistance requirements of 30 minutes is that correct that's right that's correct and having identified

02:18:31 that's correct and having identified that gap it's your evidence that the inquiry should recommend the gas industry an associated manufacturers ensure that the standards for the components of the domestic meter installation

02:18:42 installation other than the meter itself address fire resistance is that correct

02:18:48 yes um now that it's been pointed out that there is a british standard for gas pipe work for buildings up to

02:18:59 for gas pipe work for buildings up to five

02:19:00 five bar called uh bsen 1775 2007. if we can just go

02:19:05 just go to that it's at bsi four zeros one seven seven four

02:19:16 there we have it gas pipe work birth supply gas pipe work for buildings functional recommendations and if we look at page 10 paragraph 3.2.1

02:19:30 it defines pipe work as the assembly of pipes and fittings and it includes regulators

02:19:39 within that definition we can see that at the top of the page and then on page 16 paragraph 4.4

02:19:50 it says protection in case of fire that the designer shall consider the possibility of an outbreak of fire within a building containing installation pipe work that may cause damage to the fabric of

02:20:01 that may cause damage to the fabric of the building and consequently or separately to the installation pipe work and then it says the design objective should be to minimize the likelihood of an explosion or serious aggravation of fire

02:20:13 fire and beneath that we see a number of ways in which that objective can be met and the third one talks about the use of materials components and joints that would stand high temperatures

02:20:24 now it's not suggested that this goes as far

02:20:27 far as the recommendation you've made which is to have a specific standard for regulators and other meter components it it doesn't set out any specific fire resistance requirements but in addition to your

02:20:39 requirements but in addition to your recommendation do you consider that there's an opportunity to cross reference to this british standard or perhaps even to develop this standard further well this standard is currently being

02:20:50 well this standard is currently being looked at by the french because it's an en standard um without looking at it from the perspective of hydrogen

02:21:02 the it's a functional standard it may some will argue i believe that's having an automatic means of

02:21:13 that's having an automatic means of isolation at the meter i.e a thermal cutoff device actually meets that requirement of this particular clause so that's

02:21:26 clause so that's can be thrown into the mix if you're going down this route of um uh looking at bsen 1774. um the

02:21:40 um the i i certainly i am of the view that it's having a regulator that can melt

02:21:47 um in in a fire as we we saw at grenfell given that the components on either side we've got some fire resistance it's a weak point in the system yes

02:21:59 it's a weak point in the system yes thank you

02:22:02 and the

02:22:07 concern is that yes they're made of aluminium alloy

02:22:13 they're also used across europe i believe in the same material and so you'll have manufacturers who may not be willing to make them as fire resistance

02:22:25 make them as fire resistance an argument that's been put to me

02:22:29 nevertheless i think it is something that needs to be tackled

02:22:34 possibly by well i say in the first instance by saying um that

02:22:41 um that uh the regulator should be fire resistant

02:22:46 resistant the recommendation i've used the word should be addressed yes and so a viable alternative such as a an automatic means of isolation

02:22:58 a an automatic means of isolation could be argued as meeting that objective

02:23:03 objective yes thank you but yes thank you um so those are all the recommendations you proposed um final question for me it's also been

02:23:14 um final question for me it's also been proposed that high-risk buildings with multiple occupations should have a record of engineering information relating to the gas services stored in a predetermined location

02:23:26 predetermined location known to or made known to maintenance engineering and construction contractors so that they are fully informed about the gas service services in that building you haven't

02:23:38 services in that building you haven't made a recommendation like this but is that something that you would support and you would think that was a good idea yes it will be covered in the edition three of g5 right thank you mr chairman i've come to the end of my

02:23:50 mr chairman i've come to the end of my pre-prepared questions sorry i've finished slightly later than i meant to but it's been good to get that topic dealt with right well thank you very much mrs hancox at that point as you probably

02:24:01 mrs hancox at that point as you probably know we have to have a short break says that council can check nothing's been left out and also so that others who are not here but are taking a keen interest in our proceedings can make suggestions for any

02:24:13 proceedings can make suggestions for any further questions that perhaps we ought to put to you so we'll

02:24:17 we'll we'll break now for 10 minutes and come back at 25 to 5 and see if there are then

02:24:23 then any more questions for you all right thank you very much

02:24:35 right well we'll break 25 to five thank

02:24:40 you

02:36:13 yes would you ask mr hancock's to come back in please

02:36:28 right with 10 let's see if there are more questions for you yes just one question mr chairman um we've heard in your evidence that in your opinion there was in 2016 and 2017 a gas

02:36:39 2017 a gas industry-wide knowledge gap about the importance of fire prevention and mitigation measures um do you have any recommendations for the chairman as to how this might be addressed or

02:36:50 addressed or improved within the gas industry i believe that will be addressed by the work that's being done by the construction

02:37:01 construction industry

02:37:07 looking at the competence not just of building engineers

02:37:15 fire risk assessors etc a lot of work going on

02:37:19 going on with that there will be a gas cohort in that uh and i'm aware of what what's going on there so i think that is being covered

02:37:32 there so i think that is being covered by the

02:37:33 by the um effectively through the building safety regulator stuff but but yes we address in the update of g5 certain fire safety stuff

02:37:46 certain fire safety stuff like fire stopping and

02:37:49 references to all the difference between react reaction to fire tests and fire resistance tests yes which barbara lane gave your presentation

02:38:00 presentation to the inquiry about um and that will be being picked up there yes so i think from what you've said you're satisfied that the gas industry is

02:38:12 satisfied that the gas industry is already responding to this recognition that there was a gap in its knowledge yes yes yes thank you it's going to take time to

02:38:21 time to fill that gap but we've identified it and work is going on yes thank you yes thank you mr chairman those are the end of the questions i'd just like to thank mr hancox for all

02:38:32 i'd just like to thank mr hancox for all the considerable help and assistance he's provided to the inquiry we really really appreciate it thank you well it's right that i should add the thanks of all three of us on the panel to what ms grange has said

02:38:44 panel to what ms grange has said we can see how much time and effort has gone into

02:38:47 gone into helping us and producing detailed reports more than one um speaking for myself they've been very illuminating and interesting and we really are very

02:38:58 and interesting and we really are very grateful for all the help you've given us

02:39:00 us and um and for the time you've offered us to come and give your evidence today so

02:39:05 so thank you very much indeed thank you now you're free to go right thank you very much thank you

02:39:20 right ms grange well that must be it for today it's it and it concludes the gas evidence

02:39:26 evidence and i think you have evidence on lifts i believe tomorrow we have other witnesses to come tomorrow to deal with other subjects yes you do all right well thank you very much well

02:39:35 much well we break there for the day and we shall resume at 10 o'clock tomorrow morning with another witness good thank you