Gas Explosion

[sartorst]

In my search for a boat the owner was proudly showing me the new propane stove he had installed because the previous pressurized alcohol was ( SO dangerous) on further inspection I found that the gas line led to a small rusty propane bottle with 3 spares laying in a locker also very rusty!! The guy claimed to be a retired fire chief! must have forgotten a few things since his retirement

[SvenG]

Originally Posted by Blue Crab

ETA: Tue. Dec. 17 - Fri. Dec. 20

SHIPPED: NEW ORIGO Alcohol Stove Model 1500

-Sven

[old pirate]

Originally Posted by seacap

We had a huge explosion on a 33' sloop here on st. Thomas. The guy killed his best friend and his dog. The owner ended up in the hospital. The boat was a wreck. You could hear the explosion for miles.

They had set off 2 bug bombs (new meaning to the phrase), which even one in that small space is overkill (sorry for all the puns). I heard there was a gas water heater on board with an open flame (which would be a bad idea too), but have no confirmation. Well something set it off.

Was very sad.

Hi seacap
We were anchored off the Ramada that day and were bringing the dink ashore at the time of the explosion. Had to alter coarse to collect a very stunned dog from the water. The vet had to put him down because of the internal injuries. As I remember they had just started cooking breakfast, thus the dog in the companionway. Very sad.
The gas had built up overnight from the bug devices and (memory gets me) it was (northern) winter so the hatches might have been closed ? Good ventilation might have prevented this accident.

[delmarrey]

Originally Posted by Ocean Girl

I did not think a portable 16oz tank could do that, gulp.

It had to be leaking in the compartment for a while. One can put a match out in propane if there's not enough oxy in ratio.

[SaucySailoress]

Originally Posted by Tony B

...and then not be able to smell the gas leak. And when you do, not worry about it.

Being unable to smell anything myself, this is a concern. I MUST order those detectors!

Originally Posted by MarkSF

That has to be a definition of lucky that I wasn't familiar with, until now.

Believe me. When you wake up in ICU, you feel lucky. You're alive.

[shorebird]

Propane is a very safe fuel, when installed and handled properly. It is widely available, and provides a clean burning flame for cooking on board. Proper installations are, however, rather expensive, (what isn't on a boat?) and tempting shortcuts can lead to disaster. There are no shortcuts, no money to save, no "used" bits and pieces at the marine junkyard which will save $$$, you just have to pony up and do it right, or use another fuel which is a little more forgiving. BTW, Westmarine has all the bits you need, along with instructions online to help in a propane installation.

[klmmicro]

Plumbing out a propane line to a stove is easy. Properly dope the connections and make sure that there are no chafing points as you pass through bulkheads and such. Check things regularly. It is not that hard to install, use and maintain a propane based system safely. Things are evening easier if the bottle is connected directly to your stove...

[shorebird]

I do not believe compression fittings should be "doped." Can you elaborate what you mean by connecting directly to your stove?

[klmmicro]

Originally Posted by shorebird

I do not believe compression fittings should be "doped." Can you elaborate what you mean by connecting directly to your stove?

I can do that. I have a pack stove that screws directly to the gas canister. No hose or extended line to consider. There are lanterns and heaters that do this as well. You have to pay attention to the seals is all.

I work in the appliance industry and dope all of my connections for both NG and LPG. Yet to have a leak doing it. Course, this is not using a hose as you might find on a BBQ but hard lines.

[hellosailor]

kim-
Screwing directly into the bottle does not assure safety. The problem is that the "valve" in the one and two pound propane bottles is not a real valve. There's just a rubber ball, held up by the gas pressure, in the neck of the bottle. The bottles aren't machined very finely, the rubber balls aren't prize quality, and sometimes, they simply leak from the factory, or leak after the first use has disturbed them.
I took a couple of bottles (propane and map and oxygen) out of a storage closet recently. They were empty. They sure weren't empty when I stored them.

As discussed elsewhere online, there are brass caps with o-ring seals for those bottles, about $10/2, which boaters probably should consider mandatory for any bottles in storage.

[shorebird]

When using hard lines, normally a tapered thread, both thread sealant and/or teflon tape can be used, and should be used, but compression fittings should seal without using either. I'm no expert, but I think teflon tape is not indicated for compression fittings, and can cause leaks, while properly rated thread sealant will neither help nor hinder the joint. Storing and using a portable gas cylinder without an overboard vented locker, is, IMHO, not safe or approved, since any accidental venting of propane will collect inside the boat instead of sinking through the locker vent to the outside. This is assuming you are using the appliance inside the vessel. As I posted, I once opened our LPG locker to find a disposable cylinder hissing away like no tomorrow, venting propane at an alarming rate. Now having said this, you may be fairly safe, given your experience within the relevant industry, but I still insist, to maintain a level of safety, only proper installations done to "code" are safe and consistent, and provide a level of safety to the masses whose IQ may be less than their age.
Cheers.

[captain58sailin]

They make a special pipe dope just for propane fittings. I don't know about down south, but here we can get it at the local hardware store. All I've heard about teflon tape, is it is a bad idea with propane.

[Blue Crab]

My new Origo has arrived. Not yet installed but I feel better already.

At coffee time this a m, I reached thru the hatch to turn on the flow from my 11# fiberglass propane bottle ... but ... heh ... it was already on.

Between my casual attitude about life in general and age-related Alzheimer's, I'm thinking I can live (no pun) with an extra minute to heat coffee.

One thing I need to modify is I can't quite turn off the stove if I'm on the composter.

Life is little things.

[pbiJim]

Compression fittings do not need any sealant. I have successfully used them on 3,000psi helium lines in medical equipment. Helium molecules are only 2 atoms wide. If helium can be sealed in without leaks, then bigger molecule gasses should be easy to contain.

[Nicholson58]

I just yesterday read an old paper copy of a story on a Royal Navy training vessel Camper-Nicholson 55 ketch that was destroyed in its slip in a propane explosion. The particulars were:

Two propane tanks connected through a Y to a regulator.
Copper line to the gally stove.
Tank ran out in the PM so tank valves were switched to the full tank.
Installer of the second tank had failed to get a wrench to tighten the fitting.
The locker (vented overboard) was not totally sealed and so permitted propane into the below deck space including engine room.
The generator was started (diesel) remotely. Determined to be the spark.

The explosion split the deck & tore out bulkheads. The hull was compromised.
One person lost part of a leg.
One person ruptured both eardrums.
Boat destroyed.

Note that a solenoid shut-off would not have prevented this.

This took a combination of human and mechanical errors. There is nothing that worries me more than the possibility of fire & explosion. We are a Camper-Nicholson 58 ketch of about the same vintage with a few things modified. So this article got my attention. Our two 10# tanks are in a tiny locker within the lazerette. Tanks feed a common regulator through seperate hoses. Each tank has its own pressure gauge. There is a solenoid shut-off between the regualator & the boat. The locker is gasketed and vented overboard. SInce we ALWAYS shut off the propant tank valves and close the locker & lazerette hatch, we must stick our head back into the locker to re-open the tank valve. The solenoid's breaker is kept off. The gas valve switch in the gally (below the counter on the right) is off when we are not cooking. There is also a manual shut-off hand valve in the copper line from the regulator where it enters the cabin. (small locker beyond the admiral's nose) All is always off when the gas is not in use.