Path: utzoo!utgpu!watserv1!watmath!att!cbnews!military
From: terryr@ogicse.ogc.edu (Terry Rooker)
Newsgroups: sci.military
Subject: Re: Ship survivability (USS Midway)
Message-ID: <1990Jul6.032713.27556@cbnews.att.com>
Date: 6 Jul 90 03:27:13 GMT
References: <1990Jun30.053912.4518@cbnews.att.com> <1990Jul5.020444.14132@cbnews.att.com>
Sender: military@cbnews.att.com (William B. Thacker)
Organization: Oregon Graduate Institute (formerly OGC), Beaverton, OR
Lines: 44
Approved: military@att.att.com



From: terryr@ogicse.ogc.edu (Terry Rooker)
In article <1990Jul5.020444.14132@cbnews.att.com> wrf@mab.ecse.rpi.edu (Wm Randolph Franklin) writes:
>
>
>Some naive questions from someone who's never been in the Navy:
>
>1. Standards  for  buildings on land  often  require a heat  detector in
>every storeroom.  Why don't ships do this?  Would the  extra wiring pose
>a greater threat than the earlier notice?  Would there be too many false
>alarms?
>
Such detectors are possible, and are used in critical spaces.  To
supplement such protection there are a lot of watches on board a naval
vessel, part of whose job is to watch for fire/damage.  Every time you
run a wire through a deck or bulkhead you increase the difficulty of
the damage containment problem.  A single compartment burning or
flooding does not threaten a ship.  It is the progression of the
fire/flooding that will sink it.  So the general rule has been to
limit cable runs and piping as much as possible.

>2.  Why isn't Halon used?  It's used  in computer  rooms on land.   It's
>supposed  to  quench  most fires at  a  concentration not (immediately?)
>fatal  to people?   If it's  a  war,  the immediate danger  of  the ship
>sinking is greater than the danger  of future cancers (the  Agent Orange
>argument).  Note that I'm  not certain that Halon is  a long term hazard
>to people.
>
Halon is used more often.  Before that there were CO2 smothering
systems.  Due to the nature of ship construction there are numerous
small compartments.  For damage containment reasons, it is not
practical to have a central station with connections to every
compartment.  Weight and space reasons preclude equiping every
compartment with its own smothering system.  The compromise is to
equip high risk compartments (ammo spaces, engineering spaces, etc)
with installed fire detection and extinguishing equipment.  General
storerooms are not considered high risk.



-- 
Terry Rooker
terryr@cse.ogi.edu