Re: [VAC] battery hazard

[Ebert Steele <k5cad@xxxxxxxxxxx>]

Large businesses insure there investments based on a simple
formula -- Probability X Seriousness = Risk. An example: "The
moon might fall" falls in the category of "But it COULD happen."
But the probability is low or nonexistent, so not many rational
people would prepare for that eventuality.

But, if the question is "What if our $100 million styrene plant
exploded," the probability changes. Because there is an awesome
body of knowledge that documents the necessary ingredients for
such an event. That too, is simple. The ingredients needed are
fuel, oxygen, and a source of ignition.  Because it has happened
often enough in the past and will sooner or later happen again,
they buy or set aside funds as insurance for styrene plant to
keep them whole in the event of a loss. Then to reduce the
probability of such an event they engineer all kinds of safety
devices and procedures and conduct continual safety training in
an effort to keep those critical three ingredients from coming
together. 

In the case of our battery scenario, the probability and
seriousness have been questioned on this list. Hydrogen, when
reaching the critical mixture with Oxygen, will explode if there
is a source of ignition. 
That's not an "urban legend." That's a fact. To reduce the
probability, one needs to take away one or more of those three
critical elements. You can take away the oxygen (the critical
ratio of hydrogen and oxygen) by venting to the atmosphere. You
can reduce the probability of a source of ignition by making sure
the battery is secure and doesn't cause a short external to the
battery. 

I once worked in a facility that manufactured, among other
things,  hydrogen cyanide. I learned to be a "Nervous Nellie." 

For that large chemical company the seriousness was measured and
pegged at $100 million. For me, the seriousness is the safety of
my family. In addition, the probability is that it has happened
often enough before to make me nervous. That is a very personal
choice that I have not made for anyone except me and my family.
Therefore, I will never install batteries in a compartment that
is not vented to the outside atmosphere.
  
If that makes me a "Nervous Nelly" that's OK because I know that
my family is a little bit safer. 

Thanks for listening to my other 2 cents. I do sincerely hope it
is seen as a contribution to this good list. 

Ebert Steele