LETTERS TO THE EDITOR
oxygen from reaching the fire, so the
fire smothers.
Also according to the Internet:
Since water mist systems utilize
water as the extinguishing medium,
they are totally safe for humans.
These systems can be useful for
suppressing fires in gas turbine
enclosures and in machinery spaces,
and they are FM-approved for
such applications.
I hope you find the above data
interesting and useful in the future.
The author of the article in Fire
Engineering was Ronald R. Spadafora,
a New York City Fire Department
deputy assistant chief and an adjunct
professor of fire science in the
Department of Public Management at
John Jay College and City University
of New York. He or somebody
from the National Fire Protection
Association committee might know
of systems employed in yachts that
are commercially available.
Bob Frenier
Chelsea, Vermont
The subject of fire suppression
at sea is fascinating. So much so, in
fact, that I’m working on a seminar
for an upcoming Trawler Fest on this
very topic.
I’ve heard of water mist systems,
although I’ve never seen one used
on a yacht, and I believe I know why.
The systems I wrote about in my
article (PMM Sept. ’08) that use
a compressed gas have one very
attractive feature that’s tough to
beat: they require no electricity or
other energy to deploy. The gas exits
the bottle under pressure, and that’s
all there is to it. They can be triggered,
and trigger other actions such as
closing dampers and shutting down
equipment, with gas pressure alone.
(Most yacht systems use an electronic
interconnect for engine/genset
shutdown, but this can be activated
by inert gas, as well, and often is on
larger systems.)
The water mist system requires the
use of a pump, and, very importantly,
it needs water—the water in which
the vessel is floating. Presumably, the
required water would not be stored
aboard because it would be too bulky
and heavy. If the boat is ashore
when a fire occurs, no protection is
available. Finally, water mist that’s
made from sea water is corrosive and
conductive indeed. It’s not something
you’d want to spray over sensitive
electrical/electronic gear or into
running engine air intakes.
