Gas installation pipe distance to CU

[John-SJW]

The best position for a CU is in a cupboard that has a vertical copper gas installation pipe that would be about 25-80mm from a metal CU. This pipe supplies a boiler. Not a gas service pipe, or gas meter, just a copper gas pipe, with no joints, near the CU.

1) Is this OK by current regs as CUs are metal, which reduces fire hazards?
2) If not, can the section of gas pipe near the CU be in some plastic trunking, making it conform?

Thanks

 

[loz2754]

The regulation is 150mm from a gas pipe to a consumer unit. Unless there's a physical barrier between them.

 

[John-SJW]

The regulation is 150mm from a gas pipe to a consumer unit. Unless there's a physical barrier between them.

Thanks. That 150mm seems to come up a lot. Also 25mm between gas pipes and cables.

The physical barrier? Plastic trunking with gas pipe inside?

 

[loz2754]

I guess that would do it.
Although I seem to remember there may be a gas regulation that prohibits boxing in gas pipes...

 

[John-SJW]

I guess that would do it.
Although I seem to remember there may be a gas regulation that prohibits boxing in gas pipes...

Not if the trunking is open each end.

 

[loz2754]

Not if the rrunking is open each end.

That rings a bell

 

[loz2754]

Maybe one of the gas men on here can elucidate further.

 

[John-SJW]

Trunking would only be 12-18 inches long where the pipe passes the CU. Open both ends.

 

[loz2754]

Trunking would only be 12-18 inches long where the pipe passes the CU. Open both ends.

Sounds like a plan

 

[John-SJW]

So plastic 50mm x 50mm trunking is fine?

 

[Deleted account]

The regulation is 150mm from a gas pipe to a consumer unit. Unless there's a physical barrier between them.

Never seen that one before.

 

[loz2754]

Yes. At least from an electrical standpoint.

 

[John-SJW]

Trunking would only be 12-18 inches long where the pipe passes the CU. Open both ends.

They do not like gas pipes in void spaces. If running through a sleeve it has to be open one end. So gas escapes can get out and warn via the gas smell.

 

[John-SJW]

Never seen that one before.

I know it was 150mm when CUs were plastic, but they are now metal. So I wondered if the regs had taken that into account. Also does metal and RCDs make a difference. Things have moved on. I know between gas pipes and cables it is 25mm, which at times is difficult when around boiler pipes.

 

[telectrix]

my other half does not like my gas escapes escapingin the bed, especially when I pull the quilt over her head.

 

[loz2754]

The standard is BS6891. Which of course we don't have to hand....

However, the subject is covered in the on site guide published by the IET. My copy of which is unfortunately located outwith the premises.

 

[GBDamo]

Never seen that one before.

Had some gas engineers replace a gas feed into a meter cupboard. (One of the wood butchers had put his circular saw through the existing lead pipe.)

I was sticking some down lights in the same room as the were ruminating about their route.

Basically the route was straight up, through the top of the cupboard, clipped to the wall and into the ceiling. However the old lead curved round a 6" thick joist so they decided to move the pipe to the side of the joist and straight down.

Only now when it entered the cupboard it ran 50mm alongside a 1970s switch fuse.

As they were leaving they said "oh, you'll have to move that over 100mm" quoting this 150mm rule.

Now if they hadn't just have assumed I may have tried to be accommodating but thier damn cheek got the better of me.

"Not happening" I said, so they're straight on the phone to their gaffer, who no doubt phoned my gaffer as he phoned me asking me to shift the damn thing.

Whose paying the bill I ask. "What bill, its only four screws" he says.

"Well.....

One, that switch may contain asbestos, so who's paying for that assessment?

Two, their is no slack on the cable so it will need extending but digging out so the junction box is away from the gas pipe.

Three, the sub main cannot be assumed to be more than 50mm deep in the wall (could actually see it at the top of the wall) and if I start altering it I have to bring it up to regs. So I have to either chase it out and cap it or RCD it.

But, Four, can't RCD it as there are RCDs in the board upstairs and I'd lose selectivity so it will need replacing with SWA.

So those "just four screws" are looking at £400 and two days work plus decorating/making good.

I can get started in the morning if you want"


Ten minutes the plumbers phone ring, swearing and sulking and the tools come out of the van....

Thought it best to have an early dart..?

 

[brianmoooore]

So it's a gas installation reg. Anyone suggest a reason for the required clearance? There's nothing particularly vulnerable or fragile about a copper pipe, whatever is inside it.

 

[Dave OCD]

It always seems iffy to me when I see mains gas pipes running round the outside of houses at low level totally bare and unprotected. But it must be deemed acceptable ?

 

[John-SJW]

So it's a gas installation reg. Anyone suggest a reason for the required clearance? There's nothing particularly vulnerable or fragile about a copper pipe, whatever is inside it.

Well a reg is a reg. All have to conform.

 

[John-SJW]

So it's a gas installation reg. Anyone suggest a reason for the required clearance? There's nothing particularly vulnerable or fragile about a copper pipe, whatever is inside it.

A gas pipe within 50mm of a CU with no demountable joints (compression), is very safe, especially with metal CU cases and RCDs.

 

[loz2754]

Maybe it's to prevent a rogue live wire popping out when the lid is removed and causing a short circuit arc which could blow a hole in the pipe and ignite the gas. My mentor once told me he witnessed such an incident.

 

[John-SJW]

So, putting the copper gas pipe into 12-18 inches of 50mm x 50mm plastic trunking, open at each end, would satisfy the regs?

 

[John-SJW]

The standard is BS6891. Which of course we don't have to hand....

However, the subject is covered in the on site guide published by the IET. My copy of which is unfortunately located outwith the premises.

I found this. In the gas regs, not electrical. But a reg is a reg. Not sure if it is current..

BS6891-2005

8.16.2 Separation of installation pipework from other services

Where installation pipes are not separated by electrical insulating material, they shall be spaced as follows:

a) at least 150 mm away from electricity meters and associated excess current controls, electrical switches or sockets, distribution boards or consumer units;
b) at least 25mm away from electricity supply and distribution cables.

That looks like a gas pipe in plastic trunking conforms, as it is electrical insulating material.