temperature and pressure. Vapor density compared
with air is valuable in providing information on the
This volume provides an adequate source of practical
probable duration of effectiveness when there is little or
information on chemical agents and decontamination
no air movement or ventilation.
procedures necessary for technical escort team
1-2.4 Liquid Density (Compared with Water).
1-1.1 This information is a guide for the selection of
The weight of any liquid compared with the weight of an
equal quantity of water at the same temperature and
decontamination of chemical agents. It also includes
pressure. Water weighs 8.3 pounds per gallon at 70° .
associated hazards and safety precautions.
Any liquid's density (compared with water) is. used in
determining whether the liquid would tend to sink or float
1-1.2 TM 3-215, FM 21-40 and FM 2141 contain
in water or a decontaminant solution before mixing or
additional detailed information on chemical agents and
first aid; TM 3-220 on decontamination; and TM 8-285
and TB MED-282 on recognition and treatment of
1-2.5 Melting Point.
The temperature at which a solid changes to a liquid.
recommendations for improving this publication by the
individual user is encouraged. Reports should be
1-2.6 Freezing Point.
submitted on DA Form 2028 (Recommended Changes
to DA Publications) and forwarded direct to
The temperature at which a liquid changes to a solid. It
Commanding Officer, Picatinny Arsenal, ATTN:
is important to know the freezing point of a chemical
SMUPA-WD2, Dover, New Jersey 07801.
agent because dissemination characteristics vary
markedly with physical state.
The following terms are used to describe chemical
agents and their characteristics from the viewpoint of
The temperature of a liquid at which the vapor pressure
problems found during technical escort.
equals the atmospheric pressure. A chemical agent's
duration of effectiveness can be estimated when its
1-2.1 Chemical Agent.
boiling point is known. The lower the boiling point, the
higher the vapor pressure and the greater the
A solid, liquid, or gas that, through its chemical
evaporating tendency at ambient temperature.
properties, either produces lethal or damaging effects on
men, animals, plants, or material, or produces a
1-2.8 Vapor Pressure.
screening or signaling smoke.
Vapor pressure of a liquid or solid is the pressure
exerted by its vapor (after enough time has passed for it
to stabilize) at a given temperature. Vapor pressure is
The process .of neutralizing the harmful effects of a
usually expressed in millimeters of mercury.
chemical agent by covering, removing, absorbing,
destroying, or by changing into harmless substances
through action of the chemical decontaminants. Do not
confuse decontamination with detoxification which is a
This term is used to show the tendency of a liquid to
depot-type operation where all traces of the agent are
evaporate. It may be expressed as the weight of vapor
present in a unit volume of air under balanced
conditions at a specified temperature. Volatility is
1-2.3 Vapor Density (Compared with Air).
usually stated as milligrams of vapor per cubic meter
(mg/m ) of air.
The weight of any gas or vapor compared with the
weight of an equal quantity of air at the same