just wanted to clarify..unplug/pull circuit breakers/kill power source of laptop if plugged in , without a doubt , before using the halon1211 and water method..and obviously defer to firefighting professionals, but i think, if using sand or fire blanket , you still want to have laptop in a remote location, i.e. not inside home or office..
Based on my experience as a volunteer firefighter, I'd like to share some info that doesn't cost and arm or a leg...but may save both in the case your laptop/battery explodes:
Firstly, DON'T USE WATER. duh.
It's best to use a dry chemical extinguisher (type "C") on an electrical fire.
However, use a dry powder type "D" extinguisher for the dense chemical battery (NiMH, Lith-Ion, plain old alkaline, etc.). The type "D" extinguishers are designed for chemical and combustible metal fires (e.g. magnesium fires with some automobile engines). You should be able to use the "D" type extinguisher to put out electrical fires as well.
It may seem like an odd idea, but dumping sand on a chemical fire also will work to an extent. This is just a simple smothering technique. Kudos if you actually have sand nearby...
Below are a few informative websites on battery fire safety and fire extinguishers:
http://www.fireextinguisher.com/
http://www.fire-extinguisher101.com/
Energizer Lith-Ion battery material data sheet: http://www.ntsb.gov/events/2006/PhiladelphiaPA/Exhibits/350561.pdf
Woods Hole Oceanographic Institution study:
http://ehs.whoi.edu/ehs/occsafety/LithiumBatterySafetyGuideSG10.pdf
*****Other related information*****
Lithium Ion battery in cars: http://www.digg.com/tech_news/Lithium_Ion
Technology Review - Lithium Ion cars: http://www.technologyreview.com/read_article.aspx?id=17250&ch=biztech
NTSB study: http://www.ntsb.gov/events/2006/PhiladelphiaPA/Exhibits/350561.pdf

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