On Wed, 13 Oct 2004 22:05:11 GMT, "Mick Davies"
wrote:

I understand there are sniffers to detect propane build-up but if such a
pocket of collected gas is found how do you clean it out and make the boat
safe again?


Thanks,

Mick


I'm afraid the lunatic fringe contributed, so this thread
deteriorated. But to answer your question. Explosive gas
concentrations are cleared with a fan.
Such fans are fitted with flame -traps.
The principle of the flame trap is exceedingly simple - and was
implemented in the miners' safety lamp more than 150 years ago.

Two layers of copper gauze are fitted in any ventilation hole. This
extracts enough heat to eliminate ignition. You can try this at home
if you have a bunsen burner or a cooker with gas burners.
You hold the gauze above the flame, and above the gauze there is no
flame. Or if you turn on the gas, and light the gas above the
gauze, the flame does not spread below. The method is due to (Sir)
Humphry Davy, at the Royal Institution.

Brian Whatcott Altus OK

okay, people here is a bunch of blowers designed specifically to remove
explosive fumes from a bilge. They are damned hard to find so pay attention:

http://www.westmarine.com/webapp/wcs...Display?catalo
gId=10001&storeId=10001&categoryId=12111&langId=-1&subdeptNum=302&storeNum=12

note that every one is ignition protected, so have no need to be "mounted high
to avoid explosions".

Note that some are waterproof so can be mounted under bilge water. No mention
is made to how those blowers blow bilge water overboard.

note that none incorporate a flame arrester (trap? the term flame trap is
unknown to me in the context of bilges), so if you feel the need for this
"enhancement" you will have to fabricate it yourself (nobody does, but what do
they know?).


I understand there are sniffers to detect propane build-up but if such a
pocket of collected gas is found how do you clean it out and make the boat
safe again?


Thanks,

Mick


I'm afraid the lunatic fringe contributed, so this thread
deteriorated. But to answer your question. Explosive gas
concentrations are cleared with a fan.
Such fans are fitted with flame -traps.
The principle of the flame trap is exceedingly simple - and was
implemented in the miners' safety lamp more than 150 years ago.

Two layers of copper gauze are fitted in any ventilation hole. This
extracts enough heat to eliminate ignition. You can try this at home
if you have a bunsen burner or a cooker with gas burners.
You hold the gauze above the flame, and above the gauze there is no
flame. Or if you turn on the gas, and light the gas above the
gauze, the flame does not spread below. The method is due to (Sir)
Humphry Davy, at the Royal Institution.

Brian Whatcott Altus OK