Permissible drop and TT

[kirkgas]

Just to start a wee debate cause the telly is crap, this came up in college and caused a few comments,the scenario is: existing system existing appliances U6 meter, 22mm pipe, 2mb drop over 2 mins, no smell, no issues etc
The question is "MUST YOU ISOLATE THE APPLIANCES TO CONFIRM IF THE LEAK IS ON THE APPLIANCES AND NOT THE CARCASS SO YOU CAN LEAVE IT"
I want your opinion on what you must do, NOT on what you think is better, eg some say its better to isolate the appliances to confirm its not on the pipes,
My interpretation from IGE/UP/1B is
new install with or without appliances or existing install with no appliances then no drop allowed, or if the installation is existing with existing appliances and the drop is less than the table max permissible drop then the installation passes the test, therefore no further action required
Discuss

 

[mfgs]

Mfgs
You make a valid point, I leave the 2mb drop every time, as you say the next guy shuts all the appliances then confirms one of them is leaking, so he puts the boiler then cooker back in still no drop, he then opens the fire pedestal to find the 2 mb drop, as its on an existing appliance he leaves it, but where is it dropping 2 mob between the ped and inlet side of the control valve
I love this thread

Its interesting seeing everyone's views. Once you start isolating appliances to see where the leak is you really should be identifying to fixing it, there is no excuse not to.

 

[Nostrum]

No requirement to isolate unless I've missed something. All been said in previous posts. That said, if its 3-4 MB I normally do look which is above the requirements. I also ask the question 'you don't ever smell gas, do you?' Suggesting the answer is no, because as said, if you say it when they think your looking for it they will always answer yes.

Heres another one for you.

0.5mb drop with a water u guage, but customer says they can smell gas. Can you leave it, or is this classified as no discernible drop so o.k?

 

[Keefy]

It's not just the gas released you haveto worry about.
There's another safety critical issuethat might cause a problem,


The clever people that do the fancysums your talking about, are not as clever as they would have usbelieve :disappointed:


all will be revealed later :hurray:

Still waiting for the big reveal Johnny.

 

[Leo21]

If they say they can smell gas you have to investigate and rectify or make safe.
again it's 4mbar.

 

[Keefy]

No requirement to isolate unless I've missed something. All been said in previous posts. That said, if its 3-4 MB I normally do look which is above the requirements. I also ask the question 'you don't ever smell gas, do you?' Suggesting the answer is no, because as said, if you say it when they think your looking for it they will always answer yes.

Heres another one for you.

0.5mb drop with a water u guage, but customer says they can smell gas. Can you leave it, or is this classified as no discernible drop so o.k?

Don't always doubt a customer when they say they can smell gas, the smell might be blowing in through the window from next door's gas leak.

 

[Nostrum]

If they say they can smell gas you have to investigate and rectify or make safe.
again it's 4mbar.

Yes, but 0.5mb on a water gauge (or 0.25 on an electronic gauge) is classed as 'no discernible drop' so who is right?

I don't assume everyone is lying when they smell gas, but I do try and get an honest answer. As we all know, there are some people in the world who'll always try and make something out of nothing, especially if they have a gripe with the landlord (H.A in particular)

I just ask the question in a way that doesn't make it out like i'm expecting as yes.

 

[Leo21]

When you ask a private home owner. they soon back track when they realise what is required.

 

[Leo21]

Yes, but 0.5mb on a water gauge (or 0.25 on an electronic gauge) is classed as 'no discernible drop' so who is right?

I don't assume everyone is lying when they smell gas, but I do try and get an honest answer. As we all know, there are some people in the world who'll always try and make something out of nothing, especially if they have a gripe with the landlord (H.A in particular)

I just ask the question in a way that doesn't make it out like i'm expecting as yes.

Every days a school day, I didn't know they'd put a figure on no discernable drop.

 

[tamz]

It has been out for a while now Loe and is usually a question in an acs exam.
It was changed to 0.25mb a wee while back.
This is what it says about it.

Note: A movement of 0.25 mbar or less on a fluid (water) gauge is considered to be “not perceptible”. Therefore, if the gauge is seen to move, it can be inferred that the pressure within the installation has altered by more than 0.25 mbar.
It follows that, where a gauge that can register perceptible movement of less than 0.25 mbar i.e an electronic gauge, is used, the pass criteria of “no perceptible movement” has to
be considered to be a maximum of 0.25 mbar except for those gauges that read to one decimal place when “no perceptible movement” is considered a maximum of 0.2 mbar.

 

[Nostrum]

When did that change tamz, sure it was 0.5 and 0.25 before?

 

[Nostrum]

Just add (an excuse myself from being wrong!) I have used electronic gauges for a while now so the 0.25 has stuck in my head

 

[tamz]

Sometime in the last 6 years or so i think. I noticed it when i last did my acs as i wrote down 0.5 without even thinking and it was wrong. Looked it up and it is now 0.25mb

 

[stevetheplumber]

It has been out for a while now Loe and is usually a question in an acs exam.
It was changed to 0.25mb a wee while back.
This is what it says about it.

Note: A movement of 0.25 mbar or less on a fluid (water) gauge is considered to be “not perceptible”. Therefore, if the gauge is seen to move, it can be inferred that the pressure within the installation has altered by more than 0.25 mbar.
It follows that, where a gauge that can register perceptible movement of less than 0.25 mbar i.e an electronic gauge, is used, the pass criteria of “no perceptible movement” has to
be considered to be a maximum of 0.25 mbar except for those gauges that read to one decimal place when “no perceptible movement” is considered a maximum of 0.2 mbar.

another rule change to keep the training industry afloat its the same gas and the same gauge so what other reason can there be?

 

[kirkgas]

another rule change to keep the training industry afloat its the same gas and the same gauge so what other reason can there be?

Get a grip, haha, how much did the training centre make extra on each candidate by telling them the change

 

[AWheating]

Get a grip, haha, how much did the training centre make extra on each candidate by telling them the change

£1.37 ??




as regards changes : changes for the sake of safety or technical improved knowledge are welocmed. the ones i find hard to take are when they change the name of something. When i did my electrical training over a 4.5-5 year period they changed the name of the live,neautral and earth about 3 times. Each time it was "they have changed the name phase to line conductor, so we have to alter all your diagrams and books to suit" the teachers used to laugh about it because it seems to go around in circles.

 

[johnnyplumb]

Still waiting for the big reveal Johnny.

it's all in here keefy http://www.ukplumbersforums.co.uk/g...e-gas-engineers-forum/54721-let-gas-leak.html

it's a shame you wont be able to see it though hahaha

 

[tamz]

another rule change to keep the training industry afloat its the same gas and the same gauge so what other reason can there be?

Better glasses these days?

No one can tell a 0.25mb drop on a water gauge with that degree of accuracy so they now say if you see it move at all then that is a perceptible movement.

 

[kirkgas]

Better glasses these days?

No one can tell a 0.25mb drop on a water gauge with that degree of accuracy so they now say if you see it move at all then that is a perceptible movement.

That would be a rule change that would make sense for once

 

[Leo21]

Just for once I'm spot in, never heard of the permissible drop rule . Thought a drop was a drop, for once I'm right. Yay.

 

[Nostrum]

Unless its 0.25mb or under though Leo :smug:

 

[kirkgas]

Just for once I'm spot in, never heard of the permissible drop rule . Thought a drop was a drop, for once I'm right. Yay.

Sorry, but if you have passed your CCN1 you HAVE heard of permissible drop, you may have forgotten but you did answer questions on it on your theory

 

[Nostrum]

Kirk, what is your opinion on the question I raised at the end of post #62 albeit with the wrong figures. If I had a drop on an electronic gauge of 0.2mb but the customer could small gas (unlikely I guess) would you cap or would you class as no perceptible movement?....

 

[Leo21]

Sorry, but if you have passed your CCN1 you HAVE heard of permissible drop, you may have forgotten but you did answer questions on it on your theory

I,ll take your word for it, I'm not known for my memory.

 

[kirkgas]

Kirk, what is your opinion on the question I raised at the end of post #62 albeit with the wrong figures. If I had a drop on an electronic gauge of 0.2mb but the customer could small gas (unlikely I guess) would you cap or would you class as no perceptible movement?....

That's easy peasy, ANY smell of gas means there is a leak, if its less than perceptible movement then the leak could be on the other side of the reg which has locked up,
If its a theoretical question I would say its very unlikely to smell gas that's less than 0.2mb over 2 mins, but its straight forward by the statement that they smell it so there is something to be rectified

This leads to another question scenario:
As you have said, they smell gas but there is no movement on the u gauge, what is the procedure you MUST carry out

 

[Rickster123]

That's easy peasy, ANY smell of gas means there is a leak, if its less than perceptible movement then the leak could be on the other side of the reg which has locked up,
If its a theoretical question I would say its very unlikely to smell gas that's less than 0.2mb over 2 mins, but its straight forward by the statement that they smell it so there is something to be rectified

This leads to another question scenario:
As you have said, they smell gas but there is no movement on the u gauge, what is the procedure you MUST carry out

Post a business card through the neighbours door?

 

[kirkgas]

Post a business card through the neighbours door?

Haha, could be part of a procedure

 

[Spanner2k7]

Just to throw one out there,

On a cloudy day you bring your manometer to 20mb, it sunny and rises 2mb, the cloud comes over and drops 3mb, or you raise your manometer to 20mb whilst it is cloudy, it drops 2 mb, then the sun comes out and raises it by 3mb??

Do you define that a leak or not??

 

[Mike Jackson]

This leads to another question scenario:
As you have said, they smell gas but there is no movement on the u gauge, what is the procedure you MUST carry out

If there is no movement on the gauge then there may be a leak upstream of the ECV or coming from an adjacent property. The only correct course of action is to call the gas transporters emergency number and report an uncontrolled leak.

 

[kirkgas]

Just to throw one out there,

On a cloudy day you bring your manometer to 20mb, it sunny and rises 2mb, the cloud comes over and drops 3mb, or you raise your manometer to 20mb whilst it is cloudy, it drops 2 mb, then the sun comes out and raises it by 3mb??

Do you define that a leak or not??

I do all my testing in scotland, what is this thing "sunny" you speak of?

 

[kirkgas]

If there is no movement on the gauge then there may be a leak upstream of the ECV or coming from an adjacent property. The only correct course of action is to call the gas transporters emergency number and report an uncontrolled leak.

Correct,
But when asked, a lot of re-assessment guys say they test the install and if there is no leak found they tell the customer they don't know what they are smelling as it isn't gas :-o