TM 5-683/NAVFAC MO-116/AFJMAN 32-1083
(2) LPG systems shall have approved contain-
11-3. Lighting ballast.
ers, valves, connectors, manifold valve assemblies
Since the capacitor of the ballast in fluorescent lamps
contains a small quantity of PCB the EPA has laid
(3) LPG systems shall meet all Department of
out regulations for the disposal of lighting ballast:
a. If the PCB lighting ballast is leaking the dis-
(4) LPG containers and vaporizers shall have
posal is regulated under the Toxic Substance Con-
at least one approved safety relief valve.
trol Act (TSCA). The leaking ballast must be incin-
(5) LPG shall not be stored within buildings.
erated at an EPA approved incinerator.
(6) LPG storage locations shall be equipped
b. If the PCB lighting ballast is not leaking the
with at least one 20-B/C rated fire extinguisher.
disposal is not under the TSCA. Check with your
c. Natural gas (methane). Under normal storage
local EPA office to find out any requirements in your
and handling conditions, natural gas is stable when
area for the disposal.
contained. But when mixed with air or other oxidiz-
ing agents, it readily becomes flammable or explo-
11-4. Flammable liquids and gases.
sive. Natural gas is lighter than air and can be an
Flammability is the capability of a substance to
asphyxiant by displacing air. The following precau-
ignite easily, burn intensely and spread rapidly. Ex-
tions must be observed.
treme caution should be taken when storing and
(1) Cylinders must be stored in well ventilated
handling flammable materials, follow the National
and low fire hazard areas.
Fire Protection Association (NFPA) Standard 251.
(2) All lines and equipment used with natural
Of the flammable and combustible liquids and gases
gas must be grounded to prevent static sparks.
in use, the most common are liquid hydrogen, liqui-
(3) Smoking must not be allowed. '
fied petroleum gas and natural gas (methane).
(4) Non-sparking tools must be used.
a. Hydrogen. Liquid hydrogen, like other cryo-
11-5. Toxic materials.
genic liquids, presents a hazard due to its extremely
low temperature, and the high pressures that can
Toxicity is the degree to which a substance will
be generated if it is allowed to evaporate in a con-
affect living cells under certain conditions. It is de-
fined space. However, the major hazard lies primar-
pendent upon the dose, rate, method and site of
absorption. It is also dependent upon the health,
ily in the wide ranges of flammability and deton-
tolerance, diet and temperature of an individual.
ability of gaseous hydrogen in air. The principal
Physiological effects result from inhalation, inges-
method of preventing hydrogen gas ignition or deto-
tion or absorption of a toxic material. To limit this
nation is by diluting the gas below the lower limit of
exposure, smoking and eating are not permitted in
flammability and eliminating all sources of ignition.
hazardous areas, and personnel are required to
This can be accomplished by:
wash their hands thoroughly before eating, smoking
(1) Providing adequate ventilation.
or using toilet facilities.
(2) Avoiding areas where pocketing may occur.
a. Mercury. Mercury metal is a distinct hazard
(3) Minimizing confinement.
because of its property of vaporization at room tem-
(4) Limiting the amount of liquid hydrogen at
perature. The rate of evaporation increases with
any one location.
temperature and with the surface area exposed.
(5) Using non-sparking tools and explosion-
This property is of great importance since mercury
can seep into human skin. Mercury or metal con-
(6) Grounding equipment properly.
taminated with mercury should never be heated
(7) Avoiding open flames.
without providing exhaust ventilation or approved
(8) Observing no-smoking rules.
b. Liquified petroleum gas (LPG). LPG is a dan-
b. Solvents. Special precautions should be taken
gerous fire and explosion hazard when released in
when working with solvents due to potential toxic
air. Vapors may flow along surfaces for substantial
affects and flammability characteristics. Protective
distances, reach a source of ignition and flash back.
LPG is also an asphyxiant. It is heavier than air,
measures include providing plenty of ventilation or
and may accumulate in pits and other low lying
respirators; using rubber gloves, chemical safety
areas where it may displace air. Contact with liqui-
goggles, and face shields; and providing for immediate
fied gas can cause frostbite. The following special
availability of emergency eyewash facilities. Trichlor-
precautions must be observed:
ethylene and perchloroethylene are solvents sus-
pected of being carcinogenic. The use of carbon tetra-
(1) LPG must be stored and used in wel]-
ventilated areas, and kept away from heat, ignition
chloride as a solvent is prohibited. Acute poisoning
sources, and oxygen and chlorine cylinders.
caused by prolonged inhalation may result in death.