Gas Safety

[journeyperson]

I was on a gas safety course today, mainly about natural gas supply and appliances in houses, but it touched on LPG. Caravans have low level vents which allow any unburned gas to find its way out of the van. It made me think that even if my boat is gas leak free, over time some gas is likely to buid up in the void below the floor which is maybe a couple of inches deep and there is no way to get it out, or is there? I have a dry bilge and no pump.

 

The guy running the course told us that where LPG is found to have built up in cellars beneath houses it can be emptied using buckets - scooping up buckets of air (actually heavier than air gas), carrying it upstairs and emptying it outside.

 

If you were looking out of your window and you saw a guy doing that you would probably call social services' mental health team.

[estwdjhn]

This is the main why the BSC is so obsessive about gas leaks.

 

That said, I don't know how many boats have actually exploded for this reason without a major gas leak.

[Guest]

I was on a gas safety course today, mainly about natural gas supply and appliances in houses, but it touched on LPG. Caravans have low level vents which allow any unburned gas to find its way out of the van. It made me think that even if my boat is gas leak free, over time some gas is likely to buid up in the void below the floor which is maybe a couple of inches deep and there is no way to get it out, or is there? I have a dry bilge and no pump.

 

The guy running the course told us that where LPG is found to have built up in cellars beneath houses it can be emptied using buckets - scooping up buckets of air (actually heavier than air gas), carrying it upstairs and emptying it outside.

 

If you were looking out of your window and you saw a guy doing that you would probably call social services' mental health team.

Canvas buckets if I remember correctly? How do you know how much, or if you have any gas in the bucket? Alternative methods are turning the boat upside down, or sinking it.

[journeyperson]

Canvas buckets if I remember correctly? How do you know how much, or if you have any gas in the bucket? Alternative methods are turning the boat upside down, or sinking it.

 

 

That could work. When you get your boat out of the water for blacking it could be placed in a cradle which would rotate through 180 degrees and left for a day or two. You would be able to black the bottom during that time. You'd need to remove anything from inside that isn't fastened down - and empty the diesel, water, sump oil.........thinking about it.....I'll just sink it.

[Guest]

That could work. When you get your boat out of the water for blacking it could be placed in a cradle which would rotate through 180 degrees and left for a day or two. You would be able to black the bottom during that time. You'd need to remove anything from inside that isn't fastened down - and empty the diesel, water, sump oil.........thinking about it.....I'll just sink it.

I like the idea of blacking the bottom plate whilst the boat is inverted. Reminds me of when people used to build such devices for inverting cars (usually Minis) to carry out extensive welding on the underside.

 

[Robbo]

Use a match, that will soon get rid of the gas.

[Smelly]

Won't diffusion and vents, even at door height, get rid of the little bits that inevitably escape the cooker?

[journeyperson]

Won't diffusion and vents, even at door height, get rid of the little bits that inevitably escape the cooker?

 

Maybe that's what happens and I'm not really worried, most boats have gas and as estwdjhn said above, not many explode. I've fitted one of those Lidl gas detectors and I don't really expect it to go off unless a true leak occurs.

[Dominic M]

Won't diffusion and vents, even at door height, get rid of the little bits that inevitably escape the cooker?

That is certainly the view of several surveyors I know, including two with CORGI registration. A vented bilge will see any small amounts of stray lpg disperse. Ducting a forward vent directly into the bilge has always struck me as a good idea; you cannot get more low level than that - but maybe the venting happens anyway.

[alan_fincher]

Canvas buckets if I remember correctly? How do you know how much, or if you have any gas in the bucket?

Put a lighter in each scoopfull as you are about to throw it overboard.

 

When they stop going "whoompf", you can stop bailing.

[Keeping Up]

Use a match, that will soon get rid of the gas.

But make sure that it's a safety match

[Guest]

Put a lighter in each scoopfull as you are about to throw it overboard.

 

When they stop going "whoompf", you can stop bailing.

I used to know a lad who did a trick with a lighter and gas which went whoompf. It wasn't propane though, and he didn't get it from a bucket either

[carlt]

Next time you're in dock drill a few holes in the bottoms, for the gas to drain away.

[Neil TNC]

I used to know a lad who did a trick with a lighter and gas which went whoompf. It wasn't propane though, and he didn't get it from a bucket either

 

In a past life, when I had a bodyshop, the lads used to initiate a young (smoker) appentice to coffee braek by the following method:

Up turn plastic drink cup and fill from underneath with acetylene. Place cup up turned on "coffee table", near to where apprentice normally sat. Inevitably he would reach down with his lit cigarette....

[GRPCruiserman]

Small boats have the advantage that they have a 'bung' and when I took the Yeoman out of the water I always removed the bung allowing any bilge water (and gas) to drain away.

 

You should alway light the match before you turn on the gas on the stove to 'catch' all the gas that comes out.

 

Having said that, unless you get a bad leak, as posted earlier, the gas gets diluted by the air and as long as the bilge is vented the gas should never build up to dangerous levels. Before the days of thje BSC, I had a Norman 20 which didn't actually have a gas locker, the bottle was just next to the cooker on board and it never blew up over a number of years. My parents have had boats with gas bottles in board too.

 

All my powered boats have used petrol as their power source which again has highly explosive fumes that are heavier than air and can accumulate in the bottom of boats, but again I've never had an issue and you can leagally have your outboard fuel tank wherever you like on the boat whilst it's 'in use' to quote the BSC regulations, which acknowledges the fact that the risk is not actually that high.

 

I would always refuel off the boat as this is a time when most petriol fumes detach themselves from tjhe petrol itself, and similarly a certain amount of gas always escapes when changing bottles; but I wouldn't get too hung up on it; it's big news when explosions occur and the main thing is to watch for leaks occuring, always turn the gas off when it's not needed or you're not on the boat; and keep your nose peeled, you can at least smell propane so be careful if you do.

 

Either that or go gasless if you get really worried, but gasless boats usually need larger stacks of batteries which will need venting upwards so lets hope you dont smoke!!

 

I did know one guy who left his gas fridge on which was mounted in the cockpit whilst he fefuelled his petrol boat also in the cockpit and he did experience quite a flash when the fumes ignited, but he put the fire out pretty quick; but that just goes against any common sensel and his set up regarding the fridge would no longer be allowed these days anyway; it was about 15 years ago, but shows what can happen if you're not careful or are not aware of the risks.

[homer2911]

I was on a gas safety course today, mainly about natural gas supply and appliances in houses, but it touched on LPG. Caravans have low level vents which allow any unburned gas to find its way out of the van. It made me think that even if my boat is gas leak free, over time some gas is likely to buid up in the void below the floor which is maybe a couple of inches deep and there is no way to get it out, or is there? I have a dry bilge and no pump.

 

The guy running the course told us that where LPG is found to have built up in cellars beneath houses it can be emptied using buckets - scooping up buckets of air (actually heavier than air gas), carrying it upstairs and emptying it outside.

 

If you were looking out of your window and you saw a guy doing that you would probably call social services' mental health team.

 

Nah - let the gas collect in the bilge - kills the rats see.

[ChrisPy]

if you're really worried, cut a 2" hole in the floor near the appliances and stick a vacuum tube in the hole for an hour every few weeks. If you stuff the gap with something it should draw all the air/gas through from the surrounding bilge.

[Dominic M]

if you're really worried, cut a 2" hole in the floor near the appliances and stick a vacuum tube in the hole for an hour every few weeks. If you stuff the gap with something it should draw all the air/gas through from the surrounding bilge.

And as the gas gets sucked into the vacuum cleaner, a spark from the electric motor..............

[journeyperson]

Next time you're in dock drill a few holes in the bottoms, for the gas to drain away.

 

I missed that yesterday . Do I need to wait? I think there are a couple of access places where I could drill from the inside.

[Guest]

I wonder if there is a danger of gas build up from other things, like aerosols for instance, on boats?

[journeyperson]

I wonder if there is a danger of gas build up from other things, like aerosols for instance, on boats?

 

 

Beans?

[Guest]

Beans?

Not sure about the resulting gas from beans, is that lighter or heavier than air? If indeed it is heavier, we could have a problem.

[chris w]

I've fitted one of those Lidl gas detectors and I don't really expect it to go off unless a true leak occurs.

You'll find that gas detectors go off not only because of gas but also due to the presence of aftershave, deodorant, hair spray and other volatile substances. Sometimes it becomes a PITA.

 

Chris

[journeyperson]

You'll find that gas detectors go off not only because of gas but also due to the presence of aftershave, deodorant, hair spray and other volatile substances. Sometimes it becomes a PITA.

 

Chris

 

 

That's a universal problem with budget domestic detectors. I have co2, smoke and lpg detectors on the boat and something will set one of them off from time to time. At least the lpg detector has stopped ticking now.

[ChrisPy]

And as the gas gets sucked into the vacuum cleaner, a spark from the electric motor..............

if a spark from the motor will set off the gas/air mixture then the mixture is already above the LEL and you're lucky the boat didn't go bang ages ago!

 

if you're really worried put the vacuum on 'blow' for 2 hours instead.