Gas locked inside a locker

[CarpeDiem 510]

I need to build a Gas Locker for Carpe Diem.

I had planned to build a sealed locker with a drain to outside and locate this inside another locker which ultimately drains to the bilge.  The alternative is hang the gas bottle off a transom step or cut a hole in the side of the cockpit - neither ideas I like.

It occurs to me that if there is a gas leak in the locker and the alarm starts going off, one will need to open the sealed locker to investigate, this could potentially result in gas flowing into the bilges.

I am wondering if anyone knows if having a draining locker inside a non draining locker meets the regs?

Thanks

[marinheiro 359]

15 hours ago, CarpeDiem said:

I need to build a Gas Locker for Carpe Diem.

I had planned to build a sealed locker with a drain to outside and locate this inside another locker which ultimately drains to the bilge.  The alternative is hang the gas bottle off a transom step or cut a hole in the side of the cockpit - neither ideas I like.

It occurs to me that if there is a gas leak in the locker and the alarm starts going off, one will need to open the sealed locker to investigate, this could potentially result in gas flowing into the bilges.

I am wondering if anyone knows if having a draining locker inside a non draining locker meets the regs?

Thanks

here's what the gas regs say

3.4.3 Boats
A cylinder compartment shall comply with the following:
(a) Not be accessible from an enclosed section of the boat.
(b) Be designed to—
(i) house cylinders and their associated equipment only; and
(ii) allow the cylinder to be positioned in the compartment without obstructing the
drain in Item (h); and
(iii) permit easy removal of the cylinder(s) and the operation of the cylinder
valve(s).
NOTE: Consideration should be given to the location of the associated equipment when
determining the compartment size.
(c) Be constructed of material that is water and corrosion resistant.
(d) Be capable of securing the cylinder(s) when full.
NOTE: For requirements of securing method, see Clause 3.3.1.
(e) Be sealed to prevent gas vapour from entering any enclosed section of the boat.
(f) The access door or opening shall be openable without the use of tools.
(g) Where the access opening into the compartment is other than at the top, a lower
vertical return or lip of at least 100 mm shall be provided along the full length of the
opening.
(h) Have a drain in the base of not less than 19 mm diameter, which is led outboard,
without pockets that could retain water, to a point lower than the locker bottom. The
outlet shall be positioned such that it cannot be submerged.
(i) Not contain any electrical equipment other than a non-sparking shut-off device.
(j) Have a sign clearly indicating that only cylinders and their associated equipment are
permitted in the cylinder compartment.

So I think the answer to your question is no, your idea would not satisfy the regs

[Fish 0]

Hi CD,

I have been planning on doing fairly much what you are proposing. My gas locker is within the cockpit locker, that is open to the bilges. The current gas locker is sealed around the bottom and sides but open at the top. I am planning on putting a drain in the locker to go overboard.

I don't have a lot of time for regulations, I am keen to do something that increases the safety of my boat, not to comply with the pieces of paper. In my view, having a drain overboard makes the set up intrinsically safer, in that if a leak occurs it is passively directed overboard. Gas is heavier than air, that is why it sits in the bilge... To open the cockpit locker lid to access the shut off valves doesn't change any risk I feel. If you have an alarm, at least you are aware of the issue and can take other measures, such as shut down all ignition sources, evacuate etc. Not having a drained locker means your bilge and fill up while you are sleeping off the last bottle of rum, so the residual risk is far greater. I guess its the difference between complying with 80% of the requirements on a boat that predates the requirements, or attempting to comply 100%, and never actually implementing the project, so you comply with zero (and have substantial residual risk)

We always turn our bottles off manually, none of the lectrical stuff that can fail. That and my boat pre-dates gas regulations.

The other option is to get an induction cook top and ditch gas altogether. Apparently they are the latest trend in the tropics, keep the boat much cooler from wasted cooking heat. All you need is 2 tennis courts of solar and a gazzillion dollars worth of LiPeFe batteries, and some fancy controllers to stop them from catching fire... (yes, I am being factitious...) But then you can be fully off-grid.

PS, Come to think of it, I could seal the top of the locker with an insert / 2 nd lid. But that would be an impediment to turning the bottles off manually every time we use it. I wonder which is safer, a system that allows safe behaviours and good practices, or a fully sealed system that complies with the regs?

[Jon 391]

Carpe Diem

ph Angus Willison on Monday and ask him ( head safety inspector YNZ ) then let us all know.

I noticed a few of the RNI boats had a Aluminium cylinder hanging off a bracket on the stern rail

[aardvarkash10 1,057]

5 hours ago, Fish said:

 

PS, Come to think of it, I could seal the top of the locker with an insert / 2 nd lid. But that would be an impediment to turning the bottles off manually every time we use it. I wonder which is safer, a system that allows safe behaviours and good practices, or a fully sealed system that complies with the regs?

This is exactly the set-up on Stepping Out.  The gas bottle sits in a separately boxed compartment in the cockpit locker, and drains to the rear of the cockpit (open/scoop transom, so no issue there).  A simple flat lid sits in a short rebate in the top of the gas box, fingerhole to pull it up.  Closing the locker clamps the gas box lid closed as well.  Simple, effective, compliant.

[CarpeDiem 510]

On 27/06/2020 at 10:26 AM, Jon said:

Angus Willison on Monday and ask him then let us all know.

Had Angus over today to do our Cat 3 again, we discussed this.

The answer is no.

 

[Jon 391]

Now you know

[Fish 0]

I was going to reply to Carpe Diem's post with the question, would you rather do something that improves safety but does not comply with the regs, or do nothing in order to comply with the grandfather clause of the current regs.

In the commercial regulatory environment, it is harder to apply judgement and own that risk yourself.

PS, It Got, are you still having a bad day? I've been hoping you'd change your name back again, just so we know which one of your personalities we are interacting with today

 

[CarpeDiem 510]

1 hour ago, Tamure said:

I think the locker sitting inside a space that can’t itself drain is simply crossing fingers and hoping for the best. What you are expecting is that the gas leak  will not occur when the boat is heeled over or moving around in waves. You are also hoping that the gas leak will not be so much that it will overwhelm the drain.

If you are going to the trouble of building a locker then build it to spec, It’s not that hard, go for a stroll and see what others gave done on similar boats

 

Firstly the gas locker would be completely air tight except for its drain. So the fingers crossed, is that the locker door did not leak. The same principle as a Cat 0 bulk head with a air tight door.  So long as the sealed locker door was shut securely then there would be no way for the gas to get inside the boat, it would go out the lockers drain. 

As I said in the original post, I wanted to avoid cutting a hole in the side of either the cockpit or the transom.  I generally dislike cutting holes in the outside of boats. 

It's going to need a big hole next to the point where the runners attach, so the load that the runners generate will need to go somewhere else. So it will need to be appropriately designed and is probably not a diy job anymore as a result. 

While I am OK laying up glass inside the boat where it does not need to be structural I am not super keen on doing it myself at a structural location as I have no skill in laying glass to meet structural loads or even the slightest knowledge of what's required.

So unfortunately yeah, it is a bit hard now. The DIY solution to meet the spec is to hang the bottle off the pushpit... Which is what other boats like ours are doing.  So I will be engaging a builder. 

[Cantab 341]

11 hours ago, CarpeDiem said:

The DIY solution to meet the spec is to hang the bottle off the pushpit...

Like thousands of other yachts do, the safest way. 

 

11 hours ago, CarpeDiem said:

The same principle as a Cat 0 bulk head with a air tight door

But they don't stick a gas bottle in it.

 

Some of the regulations don't make too much sense, the bit about lockers does.

[Fogg 427]

The gas lockers on most recent production boats (that comply with EU regs) are in the cockpit with a sealed bottom (so nothing can get into the bulges) and a small drain hole at the bottom which goes overboard. The lid itself is a standard cockpit locker lid ie it’s not airtight. It doesn’t need to be because lpg gas is heavier than air and sinks to the bottom out through the drain hole. It doesn’t float up out through the top lid.