Flammable Gases

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

avoided.

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

materials.

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

with other materials such as flammables, oxidizers, or explosives may cause violent reactions or

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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