Mounted search and rescue

[Una Smith <una.smith@att.net>]

The subject line of this thread mentions the Heat Index.  For those not
familiar with the term, it refers to a table combining ambient temperature
and humidity.  See for example http://en.wikipedia.org/wiki/Heat_index .

The table on that page gives Heat Index numbers for 40% to 100% humidity.
Note that the Extreme Danger range of temperature varies by ~20 degress
Farenheit, depending on humidity.  Heat Index can change fairly rapidly
from one location to another and over the course of the day, so I would
not necessarily make call-out decisions based on it.  However, when giving
task assignments to field teams I certainly would take HI into account.
In terms of Incident Command System, monitoring HI during the course of
a SAR mission would be part of the job of the Safety Officer.

Physical condition and hydration level are important mitigators but in
the Extreme Danger range even well conditioned and hydrated individuals
may be in extreme danger.

Here in New Mexico humidity rarely exceeds 20% except in the monsoon
season, when it rarely exceeds 40%, so we don't even fall on the table.

        Una Smith
        New Mexico

PS:  If you want to use the Heat Index table in your own document, here
is how to do it.  From http://en.wikipedia.org/wiki/Template:HeatTable
print to a PDF file.  In a PDF editor (such as Adobe Illustrator) crop
and save the table as EPS file format, and include the EPS in your own
document.  See also http://wikimediafoundation.org/wiki/Terms_of_use .