testing for gas leaks using a bubble tester

[paul wilderness]

Thank you for all of your responses. This will be my last post on the matter

 

At the time of the test I made no comment to the examiner. I accepted his decision and said I would sort it out. Days later I realised through prior knowledge and research that his procedure was not correct and potentially damaging.    I called him and suggested that his method of checking for gas leaks was not correct. (It states all over the web that having an appliance lit is not the way)

 

The examiners reply was  'I have been testing boats for x years blah blah etc etc.  Obviously that attitude ends any possibility of reasonable discussion.

[Tony Brooks]

6 minutes ago, paul wilderness said:

 

 

The page and section numbers are all mixed up. You will find it of you keep looking. it is a PDF so you should be able to use the page number ting -top left on my computer, to go straight to page 101 in the link. It is complicated  because there is also a test for tightness between cylinder and bubble tester and the need to test that the tester has liquid in it and is working properly.

 

Did you get a proper schedule of failure or did he just stop the examination and walk away? That is the crux of the question at this time.

[nicknorman]

12 minutes ago, paul wilderness said:

Thank you for all of your responses. This will be my last post on the matter

 

At the time of the test I made no comment to the examiner. I accepted his decision and said I would sort it out. Days later I realised through prior knowledge and research that his procedure was not correct and potentially damaging.    I called him and suggested that his method of checking for gas leaks was not correct. (It states all over the web that having an appliance lit is not the way)

 

The examiners reply was  'I have been testing boats for x years blah blah etc etc.  Obviously that attitude ends any possibility of reasonable discussion.

But can you not see from the written detail of how the testing is to be conducted - ie the first step is to check that the bubble tester shows bubbles when a small appliance is on? Please read the procedure here https://www.boatsafetyscheme.org/media/299273/bss-examination-checking-procedures-interim-public-version.pdf page 102.

 

Your bubble tester is defective.

 

So bottom line I’m afraid is that the examiner is correct and you are not. Just because you “read stuff all over the web” doesn’t mean it is correct. Always look for the “horse’s mouth” ie the source data, not something someone posted somewhere, such as “yes, the earth is definitely flat”.

 

I realise you won’t enjoy reading this, you came on here hoping for sympathy but in fact you have not read what you wanted to hear and so you will not be back. It is a common problem these days.

Edited January 8, 2023 by nicknorman

[GUMPY]

This all makes me glad I don't have and never will have a bubble tester fitted.

Give me a manometer every time.

 

[nicknorman]

4 minutes ago, Loddon said:

This all makes me glad I don't have and never will have a bubble tester fitted.

Give me a manometer every time.

 

agreed!

[MtB]

9 minutes ago, Loddon said:

This all makes me glad I don't have and never will have a bubble tester fitted.

Give me a manometer every time.

 

 

 

There was of course, no reason for the examiner not to switch to using a manometer instead to check for gas tightness and therefore complete the examination.

 

(Assuming this is a leisure boat.)

 

 

[TheBiscuits]

9 minutes ago, Loddon said:

This all makes me glad I don't have and never will have a bubble tester fitted.

Give me a manometer every time.

 

5 minutes ago, nicknorman said:

agreed!

 

 

Odd.  It makes me glad I have a correctly working bubble tester which lets me do my own gas check whenever I want to, usually when swapping a gas bottle over.

[nicknorman]

2 minutes ago, MtB said:

 

 

There was of course, no reason for the examiner not to switch to using a manometer instead to check for gas tightness and therefore complete the examination.

 

(Assuming this is a leisure boat.)

 

Perhaps there is no gas test point?

[rusty69]

15 minutes ago, Loddon said:

This all makes me glad I don't have and never will have a bubble tester fitted.

Give me a manometer every time.

 

I could never figure out how one is fitted. When I looked, they all seemed to have metric fittings for imperial pipe.

[alan_fincher]

6 minutes ago, rusty69 said:

I could never figure out how one is fitted. When I looked, they all seemed to have metric fittings for imperial pipe.

 

Correct.  You need to swap the fittings to imperial ones.

It used to be possible to buy ones where the supplier had exchanged the fittings to imperial  I bought from SoCal (Southampton Calor) but that was many moons ago, and you would need to check the current position.

[MtB]

8 minutes ago, nicknorman said:

Perhaps there is no gas test point?

 

Possibly but unusual, especially if the boat pre-dates the introduction of bubble testers. There is supposed to be an inlet gas pressure test point on all gas appliances these days or so we are taught, but weirdly cooking appliances seem exempt. An inlet gas pressure test point can be used for tightness testing. The drawback is if a drop in pressure is recorded (which may be acceptable with appliances connected - there are charts of acceptable drops!) it is not possible to isolate the appliances and test just the pipework.

 

I can't actually remember about boats in particular though. Something in the back of my mind tells me the only acceptable drop over five minutes with appliances connected is still zero.

[TheBiscuits]

6 minutes ago, MtB said:

I can't actually remember about boats in particular though. Something in the back of my mind tells me the only acceptable drop over five minutes with appliances connected is still zero.

 

Appendix C, Pages 96-100 

[David Schweizer]

33 minutes ago, Loddon said:

This all makes me glad I don't have and never will have a bubble tester fitted.

Give me a manometer every time.

 

 

In agree. The transparent reservoir on my bubble tester fractured, leaking gas into the gas locker. I removed it and replaced it with a test point located close to the central heating boiler. Every examiner after that was quite happy to use a manometer, which is what the domestic gas company use to check for leaks in a house system.

[Guest]

The examiner is right, they have to ascertain the bubble tester actually works before they use it. They light a burner to similulate a leak. They press the button. If bubbles appear, the device works. 
 

They then complete the test procedure in line with BSS requirements, not the manufacturer’s instructions. 
 

Your bubble tester is faulty. It’s probably blocked with evaporated fluid - or you have in excess of 12kw of appliances installed and the BT is not in a bypass, and the flow rate has sucked the fluid up into the device where it has blocked it when it’s dried. 
 

If you take the sight glass (plastic) off, and get a mirror and look up under the metal housing, you can see the “in” and “out” gasways. The “in” is the spike in the centre and the “out” a small hole at the top of the underside. One of those will be blocked. You can unblock with jet cleaners, ideally remove the BT and do it on a bench. You can check-  it works by blowing through it without wasting a fluid sachet. 
 

If it’s been blocked for ages then it will never have bubbled if there is a leak so the ‘test the tester’ procedure is absolutely essential. I’m surprised you and your previous examiners did not know this - your system has probably never been correctly tested in this case. 
 

Perhaps when you have it disconnected, you should throw it away and employ a proper gas engineer to check your system throughly. 

Edited January 8, 2023 by Guest
Typo

[blackrose]

During the last few examinations I've had on my boat the inspector has always first tested the bubble tester with an appliance lit to make sure the bubble tester is working. Then the system is tested with no appliances lit.

 

I haven't read any instructions or guidelines, but logic tells me that this is the correct procedure. 

[blackrose]

On 08/01/2023 at 16:59, Loddon said:

This all makes me glad I don't have and never will have a bubble tester fitted.

Give me a manometer every time.

 

 

Well it makes me glad that I've got two fitted which have worked perfectly and also saved me a little bit of money on BSS tests over the past 17 years.

 

I don't know how often you do a drop test with your manometer, but I'm sure if it was me it would never get done, whereas I test my systems at least every time I change a bottle and on a couple of occasions those bubble testers have alerted me of small leaks.

[blackrose]

On 08/01/2023 at 16:27, MtB said:

 

What is the procedure in the event of an examination discovering a 'fail' point? I read sometimes of examiners terminating an inspection at the first fail point. 

 

I'd expect the examiner to complete the examination in case there are other fail points too, then issue a fail certificate listing the fail points and what needs to be done. But the OP is vague on whether this happened and he received a written fail ticket. 

 

It sounds like the examiner has condemned the entire boat.

[GUMPY]

18 minutes ago, blackrose said:

I don't know how often you do a drop test with your manometer, but I'm sure if it was me it would never get done, whereas I test my systems at least every time I change a bottle and on a couple of occasions those bubble testers have alerted me of small leaks.

I don't own a manometer, the system gets tested every 4 years and I have borrowed a manometer to check the system when I have done any work on it. Its worked that way on 3 boats over the last 30 years. Only downside is my source has retired so will have to find a new examiner in 2026 if I still have the boat.

[nottheone]

The op stated he was asked to light the cooker, does that mean the oven or the smallest ring on the hob ? Would this matter and if not why would the guidelines say small burner / pilot light ? An oven would use many times more gas than a pilot light.  Also what is the problem with metric pipe  ? As far as I can see nothing in the BSS says you cant use it or am I wrong  ? 

[Tracy D'arth]

14 hours ago, nottheone said:

The op stated he was asked to light the cooker, does that mean the oven or the smallest ring on the hob ? Would this matter and if not why would the guidelines say small burner / pilot light ? An oven would use many times more gas than a pilot light.  Also what is the problem with metric pipe  ? As far as I can see nothing in the BSS says you cant use it or am I wrong  ? 

I suspect the examiner was waiting for the non existent flame failure to cut the gas flow.  Deluded. This is not the way to test.

[nicknorman]

6 minutes ago, Tracy D'arth said:

I suspect the examiner was waiting for the non existent flame failure to cut the gas flow.  Deluded. This is not the way to test.

No, the examiner was following the correct procedure and waiting for some bubbles to appear. No bubbles appeared and the flame went out, demonstrating that the bubble tester was blocked. No leak would ever show up.

 

It is amazing how, even when clear and definitive evidence is presented, some people can manage to completely ignore what they don’t want to read. I don’t even think it’s deliberate, it happens at some subconscious level. It does seem to be a global problem these days. Rationality is so last century.

Edited January 10, 2023 by nicknorman

[MtB]

5 minutes ago, nicknorman said:

No, the examiner was following the correct procedure and waiting for some bubbles to appear. No bubbles appeared and the flame went out, demonstrating that the bubble tester was blocked. No leak would ever show up.

 

It is amazing how, even when clear and definitive evidence is presented, some people can manage to completely ignore what they don’t want to read. I don’t even think it’s deliberate, it happens at some subconscious level. It does seem to be a global problem these days. Rationality is so last century.

 

 

Equally and on the other hand, people manage to read things that were never written, then rely on them in constructing their arguments! 

 

Nowhere has the OP mentioned that bubbles failed to appear at the test stage AFAICS, just that the examiner pressed the button, the cooker flame went out (several times), then he terminated the BSS examination. 

 

Had I found the bubble tester delivered no bubbles at the proving stage, I'd have told the customer. But this seems not to have happened in this case. I think there are some facts left out by the OP, possibly, which we here are filling in for ourselves. 

 

 

 

 

 

 

[nicknorman]

22 minutes ago, MtB said:

 

 

Equally and on the other hand, people manage to read things that were never written, then rely on them in constructing their arguments! 

 

Nowhere has the OP mentioned that bubbles failed to appear at the test stage AFAICS, just that the examiner pressed the button, the cooker flame went out (several times), then he terminated the BSS examination. 

 

Had I found the bubble tester delivered no bubbles at the proving stage, I'd have told the customer. But this seems not to have happened in this case. I think there are some facts left out by the OP, possibly, which we here are filling in for ourselves. 

 

The OP was not in a position to see whether any bubbles appeared or not, he was at the hob. My take is that the hob ring  went out because no gas could flow through the tester when the button was pressed. I suppose it depends on the size of the burner and how much gas can flow through the bubble tester liquid, but I would have thought that, while the flame would decrease, it wouldn’t completely go out if the BT was working properly.

 

Even if things were exactly as reported (the examiner didn’t specify why the test was failed), Occam’s razor suggests that the examiner didn’t fail the gas system for no reason, most likely there was no gas flowing through the tester and thus the flame went out with no bubbles.

Edited January 10, 2023 by nicknorman

[MtB]

1 hour ago, nicknorman said:

The OP was not in a position to see whether any bubbles appeared or not, he was at the hob. My take is that the hob ring  went out because no gas could flow through the tester when the button was pressed. I suppose it depends on the size of the burner and how much gas can flow through the bubble tester liquid, but I would have thought that, while the flame would decrease, it wouldn’t completely go out if the BT was working properly.

 

Even if things were exactly as reported (the examiner didn’t specify why the test was failed), Occam’s razor suggests that the examiner didn’t fail the gas system for no reason, most likely there was no gas flowing through the tester and thus the flame went out with no bubbles.

 

 

I wholly disagree. I think that razor you mention belonging to that nice Mr Occam tells us there is/was a whole lot more going on than has been presented to us. If the tester was busted, Occam's razor suggests the OP would have been informed by any reasonable examiner, but it appears he wasn't. Nor was the rest of the (non gas) examination carried out.

 

Occam's razor suggests to me there was therefore, some further reason for abandoning the examination. 

 

Edited January 10, 2023 by MtB
sp

[nicknorman]

50 minutes ago, MtB said:

 

 

I wholly disagree. I think that razor you mention belonging to that nice Mr Occam tells us there is/was a whole lot more going on than has been presented to us. If the tester was busted, Occam's razor suggests the OP would have been informed by any reasonable examiner, but it appears he wasn't. Nor was the rest of the (non gas) examination carried out.

 

Occam's razor suggests to me there was therefore, some further reason for abandoning the examination. 

 

Maybe. I certainly agree that the rest of the exam should have been carried out.