Chlorine - Items with this placard are nonflammable gases with many of the properties of poison
gas materials. The greenish-yellow vapors are highly toxic and tend to hug the ground. If the
material is leaking or on fire, consider an evacuation distance of 1/2 mile.
Poison - Items with this placard are liquids, solids or semisolids. Although less dangerous than
poison gases, they are still toxic to humans when inhaled, absorbed through the skin, or ingested
(eaten). Suspected spills shall be investigated only by protected specialists and all others
evacuated from the immediate area. If material is on fire, contact with the smoke must be
Radioactive Materials - Items with this placard are materials which emit ionizing radiation that is
hazardous. The radiation is invisible, cannot be felt, and can only be detected with specialized
equipment. In the event of a suspected leak or rupture of container, personnel shall be evacuated
for several hundred yards until the area is surveyed by specialists.
Flammable Gases - Items with this placard are materials which are often ignited immediately
after a breach of the container. If ignition does not immediately occur, the vapors will often flow
until an ignition source is reached. A flashback can then occur, igniting the entire gas cloud. A
leak that has ignited should not be extinguished unless it can be stopped. Tanks containing
flammable gases that are exposed to flame impingement or intense heat may rupture violently,
producing a large fireball, and hurling fragments of the container up to 1/2 mile, or more. This
reaction should be taken into consideration in determining evacuation distances. These materials
may also be toxic or irritating and may cause suffocation by the displacement of oxygen and
frostbite injuries through contact with the liquid.
Flammable Liquids- Items with this placard are flammable liquids which give off vapors at less
than 100 degrees F and will ignite on contact with an ignition source. These vapors are usually
heavier than air and will flow into low lying areas such as ditches and ravines.
Action shall be taken to keep ignition sources away from areas of vapor concentration. Contact
with corrosive materials can cause ignition and shall be prevented.
Flammable Solids - Items with this placard are materials that can cause fires by self-ignition or
spontaneous combustion under conditions such as being exposed to air, being crushed, coming in
contact with corrosive or oxidizing materials, or outside ignition sources. When appropriate, fires
should be fought with wet dirt or sand, keeping the flammable solid isolated from other hazardous
Spontaneously Combustible - Items with this placard are liquids less dangerous than flammable
liquids due to their higher flashpoints; however, leaks, spills and fires should be handled in the
same manner as flammable liquids.
Corrosive - Items with this placard are acids or caustics in either liquid or solid form which cause
visible or irreversible damage to human tissue or severe corrosion on steel. In addition, contact
fires. If possible, spills should be contained by protected personnel. Neutralization of spilled
material may be accomplished by trained specialists using appropriate materials. Spills of
corrosive materials may produce large quantities of fumes which may be toxic and cause eye, skin,
or respiratory damage. Persons coming in contact with corrosive materials should wash
immediately with water for at least 15 minutes and then contact a physician.
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