Gas locker

[stort_mark]

Our recently purchased boat doesn't have low level vents from the gas locker. It has a Boat Safety Certificate though, but doesn't that require venting of the locker??

 

Surveyor didn't pick it up either, in his report. Am I missing something here? I'm puzzled.

[NBMike]

They are mandatory! A leaking gas bottle contains enough LPG to fill your gas locker many times over and you really don't want the overspill in your boat!

[stort_mark]

They are mandatory! A leaking gas bottle contains enough LPG to fill your gas locker many times over and you really don't want the overspill in your boat!

 

Thanks Mike. I was sure they were. I can't understand why this was not an issue for the surveyor nor the BSC??

The overspill wouldn't end up in the boat as if it overfilled it would 'leak' over the side forward of the cratch.

 

I am wondering if there is a minimum size for the vents. The gas locker was blacked shortly after we bought it....could this have covered up very small vent holes?

[O'Mali]

I would have thought the bigger the better. Most I have seen are "D"shaped on it's back shape about 2" long/wide and as close to the locker base as poss. Why not ask a canalside engineer to burn the vents for a "drink" when you get a chance.5 min job.

[blackrose]

I would have thought the bigger the better. Most I have seen are "D"shaped on it's back shape about 2" long/wide and as close to the locker base as poss. Why not ask a canalside engineer to burn the vents for a "drink" when you get a chance.5 min job.

Or why not just do it yourself with a drill and 1"dia holecutter? You could put two in each side.

Be aware that the floor of some gas lockers are below the waterline.

Edited June 23, 2009 by blackrose

[stort_mark]

I would have thought the bigger the better. Most I have seen are "D"shaped on it's back shape about 2" long/wide and as close to the locker base as poss. Why not ask a canalside engineer to burn the vents for a "drink" when you get a chance.5 min job.

 

Yes, that's what I thought. Someone is putting them in for me next week when some other work is done. They will be about 4" above the water line.

[tony collins]

Yes, that's what I thought. Someone is putting them in for me next week when some other work is done. They will be about 4" above the water line.

On our semi-trad, (gas lockers in the stern cockpit) the vent was a 1/2" bore steel pipe coming out of the bottom of the locker and through a 90 deg bend through the hull side.

 

Tony

[Radiomariner]

I am surprised. It is just about the most important thing in the BSS inspection!. The surveyor should also have picked it up. The vent might be in a difficult to see location. Try a tipping a bucket of water into the gas locker and see where it drains away to. (But for gawds sake if it does not drain away dont use an electric bilge pump to remove the water until you are sure that there is no gas there.) If you get somebody to cut holes, make sure bottles are removed first.

It might be that when the BSC was attained there was no gas on board or the gas locker located elsewhere, there should be an appliance record with the certificate nowadays. (Tells you what appliances were on board, but unfortunately not where the gas locker was located.) If there is indeed no drain, confront your surveyor and contact the BSS, this is a serious problem!

 

Edited to correct typo's

Edited June 24, 2009 by Radiomariner

[RobinJ]

Thanks Mike. I was sure they were. I can't understand why this was not an issue for the surveyor nor the BSC??

The overspill wouldn't end up in the boat as if it overfilled it would 'leak' over the side forward of the cratch.

 

I am wondering if there is a minimum size for the vents. The gas locker was blacked shortly after we bought it....could this have covered up very small vent holes?

I suggest you take out the bottles and tip a bucket of water in and see what happens?

[Gary Peacock]

If the boat did not have gas at the time of the BSS examination then that would be perfectly acceptable.

[alan_fincher]

Someone is putting them in for me next week when some other work is done. They will be about 4" above the water line.

 

Make sure any forward mounted water tank is completely full, (or, to some degree, any rear mounted fuel tank mostly empty), when assessing how much above water the base of the gas locker is.

 

You may be surprised how big a difference this can make, (i.e. quite a few inches, on some boats).

[O'Mali]

Or why not just do it yourself with a drill and 1"dia holecutter? You could put two in each side.

Be aware that the floor of some gas lockers are below the waterline.

Because IMO them hole saws are not cheap and they dont like 6mm steel unless you go slow with some cutting grease and also where they need to be is quite an awkward place to stretch with a drill unless you can put the stern well away from the bank so as to bring the bow close.

[churchward]

As always worth going to the horses mouth and read the guide. The relevant section for LPG related subjects is here.

 

http://www.boatsafetyscheme.com/downloads/...Guide_chap7.pdf

 

See section 7.3 for cylinder locker drains.

 

".....All cylinder lockers must be fitted with a drain.Cylinder locker drain outlets must be above the normal laden waterline....."

 

....Cylinder locker drains must have a minimum internal diameter of 12mm (1⁄2 in) or increased pro-rata up to 19mm (3⁄4 in).

 

1-18kg 12mm (1⁄2 in) 113mm2

19-29kg 14mm (9⁄16 in) 154mm2

30-37kg 17mm (5⁄8 in) 227mm2

38kg or greater 19mm (3⁄4 in) 283mm2

 

The above is copied from the document but it is worth reading all of it to get a feel for how they expect it to be done and maintained. There are some useful illustrations as well.

[Machpoint005]

As always worth going to the horses mouth and read the guide. The relevant section for LPG related subjects is here.

 

http://www.boatsafetyscheme.com/downloads/...Guide_chap7.pdf

 

See section 7.3 for cylinder locker drains.

 

".....All cylinder lockers must be fitted with a drain.Cylinder locker drain outlets must be above the normal laden waterline....."

 

....Cylinder locker drains must have a minimum internal diameter of 12mm (1⁄2 in) or increased pro-rata up to 19mm (3⁄4 in).

 

1-18kg 12mm (1⁄2 in) 113mm2

19-29kg 14mm (9⁄16 in) 154mm2

30-37kg 17mm (5⁄8 in) 227mm2

38kg or greater 19mm (3⁄4 in) 283mm2

 

The above is copied from the document but it is worth reading all of it to get a feel for how they expect it to be done and maintained. There are some useful illustrations as well.

 

Presumably the cylinder weight is the total of both (or more) cylinders? If you have a 13kg cylinder and a spare, it's in the 19 to 29 kg category.

[churchward]

Presumably the cylinder weight is the total of both (or more) cylinders? If you have a 13kg cylinder and a spare, it's in the 19 to 29 kg category.

Yes that is how I read it. It is the combined total of the gas cylinders you have in the locker after all either used or spare cylinder or both may leak gas.

 

The guide goes on to say

 

"Total capacity must be calculated from the sum of the capacity of all cylinders housed in the same locker.

If the locker has two or more drains, their combined area of openings should be taken account of in assessing compliance."

Edited June 24, 2009 by churchward

[GeoffS]

I just read through the BSS items too. A couple of reflections.

 

First if water gets into the locker and is able to sit and not drain totally out is that an indication that there is an incorrect design. I know my vent is at the lowest point and just on the waterline. Some of the water that does get in stays sitting in the centre of the locker.

 

Secondly there is a second drain on the opposite side but is higher than the first one. Does that seem deliberate or just an error?

 

Thirdly, and this is what has made me really stand up and take notice of this, a friend of mine last week had a terrible smell of gas. He just turned off his bottle but I urged him to get the whole thing checked out. I couldnt see a drain on the starboard side, maybe there was one on the port side, and he said he thought it was below the water line. While looking at the locker I asked why the pipes and regulator were all boxed in (because I was urging him to get the regulator checked as well as the bottle). He said it had to be recently boxed in order to pass the BSS. This seems in contradiction to:

 

"All LPG system connections and flexible hoses must be accessible

for inspection"

 

Any comments or suggestions?

[alan_fincher]

While looking at the locker I asked why the pipes and regulator were all boxed in (because I was urging him to get the regulator checked as well as the bottle). He said it had to be recently boxed in order to pass the BSS. This seems in contradiction to:

 

"All LPG system connections and flexible hoses must be accessible

for inspection"

Yes, this seems complete bo**ocks to me.

 

All the high pressure parts - pigtails, valves, changeovers, regulators, etc should be in the gas locker, properly secured, away from possible damage, but surely not boxed in.

 

The cylinders should be properly secured, so that they can't bash into the gas fixtures and fittings, but I can't see boxing them over as any solution to not securing the cylinders properly.

 

A picky BSS inspector can, and maybe will, object to anything else in the locker that could come into contact with "gas parts", even just a flexible water hose, (many people remove all such items from a locker before a BSS, or so I'm led to believe - I wouldn't know myself. )

 

On the other subject.

 

Unfortunately many gas lockers flood when underway, and sadly ours is no exception. With a well filled front water tank, our vents ship water, and the base of the locker is quite rusted as a result - something to deal with on our maintenance tasks.

 

Some time back the BSS issued warnings about long term corrosion resulting from this having penetrated the bulkhead between gas locker and the rest of the boat in some older boats. There are two dangers here - gas can get where it shouldn't and canal/river water can get where it shouldn't. IIRC boats had sunk because of severe gas locker corrosion.

 

If your gas locker vents regularly go under, then it;s well worth checking how much plating has rusted away inside the locker.

 

The main problem, frankly, is that many "modern" boats with relatively low hull sides, but high cabin sides, do not have enough depth under the fore-deck hatch to accommodate standard 13KG Propane cylinders, and still put the locker vents high enough above the cut to prevent flooding. Something to be said for having the gas elsewhere, and higher up, perhaps.

[GeoffS]

Yes, this seems complete bo**ocks to me.

 

All the high pressure parts - pigtails, valves, changeovers, regulators, etc should be in the gas locker, properly secured, away from possible damage, but surely not boxed in.

 

The cylinders should be properly secured, so that they can't bash into the gas fixtures and fittings, but I can't see boxing them over as any solution to not securing the cylinders properly.

 

A picky BSS inspector can, and maybe will, object to anything else in the locker that could come into contact with "gas parts", even just a flexible water hose, (many people remove all such items from a locker before a BSS, or so I'm led to believe - I wouldn't know myself. )

 

On the other subject.

 

Unfortunately many gas lockers flood when underway, and sadly ours is no exception. With a well filled front water tank, our vents ship water, and the base of the locker is quite rusted as a result - something to deal with on our maintenance tasks.

 

Some time back the BSS issued warnings about long term corrosion resulting from this having penetrated the bulkhead between gas locker and the rest of the boat in some older boats. There are two dangers here - gas can get where it shouldn't and canal/river water can get where it shouldn't. IIRC boats had sunk because of severe gas locker corrosion.

 

If your gas locker vents regularly go under, then it;s well worth checking how much plating has rusted away inside the locker.

 

The main problem, frankly, is that many "modern" boats with relatively low hull sides, but high cabin sides, do not have enough depth under the fore-deck hatch to accommodate standard 13KG Propane cylinders, and still put the locker vents high enough above the cut to prevent flooding. Something to be said for having the gas elsewhere, and higher up, perhaps.

 

Hi Thanks for your reply.

 

I will have another look and a strong 'chat' with him at the weekend as I was quite worried about it.

 

I will also revisit the security of mine as , although it passed a BSS last year, there are only a couple of chains that would only stop the bottles falling towards the front of the boat but not back against the bulkhead where the regulator etc is. Hmmm.

[churchward]

I just read through the BSS items too. A couple of reflections.

Thirdly, and this is what has made me really stand up and take notice of this, a friend of mine last week had a terrible smell of gas. He just turned off his bottle but I urged him to get the whole thing checked out. I couldnt see a drain on the starboard side, maybe there was one on the port side, and he said he thought it was below the water line. While looking at the locker I asked why the pipes and regulator were all boxed in (because I was urging him to get the regulator checked as well as the bottle). He said it had to be recently boxed in order to pass the BSS. This seems in contradiction to:

Many people including BSS inspectors seem to make up their own rules. I think this maybe an example. My response to someone saying that would be to ask where exactly in the BSS document does it say that this is a requirement? If they can then fair enough but if not it's not a BSS requirement.

[alan_fincher]

I will also revisit the security of mine as , although it passed a BSS last year, there are only a couple of chains that would only stop the bottles falling towards the front of the boat but not back against the bulkhead where the regulator etc is. Hmmm.

I think this is pretty marginal.

 

We used to have similar, and there is evidence from old receipts that a crude "chain through the handles at the top" arrangement was put in to satisfy a previous BSS exam.

 

By no argument could they be called anchored, and not free to move if there were a big impact.

 

They are now both very firmly held by ratchet straps round their middles. This is a vast improvement, and was explicitly commented on by our BSS man as "much better than many I see".

 

As Churchward implies - if it's in the BSS booklet, then you have to comply with it. If it's not in the BSS booklet, and you get a fail, take it up with the central BSS office. Don't be forced into doing something the book doesn't actually say, until you have had clarification why you must, (my opinion!).

[GeoffS]

Many people including BSS inspectors seem to make up their own rules. I think this maybe an example. My response to someone saying that would be to ask where exactly in the BSS document does it say that this is a requirement? If they can then fair enough but if not it's not a BSS requirement.

 

Hi

 

I totally agree with you. This topic has prompted me to look up the document and to think about the consequences, for my mate who was told thats how it had to be a just did it, and for me to make sure my installation is correct.

 

What may be ironic is that while the BSS work was carried out the boat couldnt be licensed, prompt payment discount lost and at the end of it I did wonder to myself whether the leak was caused by the installer of boxing in.....

 

I think this is pretty marginal.

 

We used to have similar, and there is evidence from old receipts that a crude "chain through the handles at the top" arrangement was put in to satisfy a previous BSS exam.

 

By no argument could they be called anchored, and not free to move if there were a big impact.

 

They are now both very firmly held by ratchet straps round their middles. This is a vast improvement, and was explicitly commented on by our BSS man as "much better than many I see".

 

As Churchward implies - if it's in the BSS booklet, then you have to comply with it. If it's not in the BSS booklet, and you get a fail, take it up with the central BSS office. Don't be forced into doing something the book doesn't actually say, until you have had clarification why you must, (my opinion!).

 

Hi

Excuse my ignorance, how do rachet straps work and how are they fixed? This sounds like a good way to go.

[bottle]

Ratchet straps vary in the way they work examples here: http://www.screwfix.com/search.do;jsession...chbutton=submit

 

but I got some recently from Lidl on special for £2 each (continuous type)

[GeoffS]

Ratchet straps vary in the way they work examples here: <a href="http://www.screwfix.com/search.do;jsessionid=XE4FJODX4DZLKCSTHZPCFFI?_dyncharset=UTF-8&fh_search=%22ratchet+strap%22&searchbutton.x=7&searchbutton.y=9&searchbutton=submit" target="_blank">http://www.screwfix.com/search.do;jsession...chbutton=submit</a>

 

but I got some recently from Lidl on special for £2 each (continuous type)

 

Hi, Thanks, now I see. I will need to check what, if anything, I can attach them too.

[alan_fincher]

Hi, Thanks, now I see. I will need to check what, if anything, I can attach them too.

I used two of this type of thing per cylinder, through the bulkhead between the gas locker and the front well.

 

It does mean there are a total of 4 "nutted" ends showing in the front well, but I was prepared to live with that for something that lashed the cylinders down 100%

 

[GeoffS]

In order to try to prevent so much water entering through the gas locker vents I had a piece of metal welded on the outside of the vents and so far it has been very successful.

 

 

I will also fit ratchet straps next week to secure the bottles properly!