Hazmat Technician flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Vapor density

Ratio of a gas's density to air; values above 1 mean the gas is heavier than air and tends to accumulate in low-lying areas, increasing inhalation risk there.

Specific gravity

Ratio of a liquid's density to water; values above 1 mean the liquid sinks, values below 1 mean it floats and can spread across a water surface.

Flash point

The lowest temperature at which a liquid produces enough vapor to ignite near its surface; a lower flash point indicates a greater fire hazard.

IDLH

Immediately Dangerous to Life or Health concentration; the maximum level from which a worker could escape within 30 minutes without irreversible health effects or escape-impairing symptoms.

LEL and UEL

Lower and upper explosive limits define the flammable range; below the LEL the mixture is too lean to burn, above the UEL too rich.

NFPA 704 diamond

Hazard marking with health (blue, left), flammability (red, top), instability (yellow, right), and special hazards (white, bottom), each rated 0 to 4.

ERG guide pages

The orange-bordered pages of the Emergency Response Guidebook give initial isolation distances, protective action, and firefighting guidance for a material.

Placard color codes

Red indicates flammable, green nonflammable gas, yellow oxidizer, white poison or corrosive, blue dangerous when wet, and orange explosive materials.

Pipeline marker

A sign along a pipeline showing the commodity, operator, and emergency phone number; it does not indicate quantity, pressure, or flow direction.

HAZWOPER 1910.120

OSHA standard covering hazardous waste operations and emergency response; sets training, medical surveillance, PPE, and site safety plan requirements for responders.

Level A protection

Fully encapsulating, vapor-protective suit with SCBA; used for the highest inhalation and skin hazards, including unknown or IDLH atmospheres.

Level B protection

SCBA with chemical-resistant clothing that provides splash protection but is not vapor-tight; used when the atmosphere is known and not IDLH.

Level C protection

Air-purifying respirator with chemical-resistant clothing; permitted only when contaminants are known, concentrations are below IDLH, and oxygen is adequate.

Decontamination corridor

A one-way flow from hot zone through warm zone decon line to cold zone; gross decon precedes secondary decon and PPE removal.

Permeation versus degradation

Permeation is chemical movement through suit material at the molecular level; degradation is physical breakdown of the material; both govern suit selection.

Combustible gas indicator

Instrument that reads percent of the lower explosive limit; requires calibration and correction factors and does not measure oxygen or toxicity.

Photoionization detector

Instrument that measures total volatile organic compounds using a UV lamp; cannot identify a specific chemical without library matching.

Colorimetric detector tubes

Tubes that change color in response to a specific chemical; results depend on correct pump strokes, tube shelf life, and calibration.

Oxygen meter thresholds

Normal atmosphere is 20.9 percent oxygen; levels below 19.5 percent are oxygen-deficient and above 23.5 percent present a fire hazard.

Confinement versus containment

Confinement keeps material within the incident area; containment stops the release at its source using plugs, patches, or clamps.

Overpack drum

A larger drum used to hold a damaged container; it must be compatible with the material and labeled with the original hazard information.

Water-reactive materials

Substances such as sodium or calcium carbide that react with water to release heat and flammable gas; never apply water to these materials.

Initial isolation distance

The ERG-recommended perimeter for a spill, commonly 50 meters (150 feet) for small spills and 100 meters (330 feet) for large spills.

Unified command

An ICS structure in which agencies with jurisdiction share command; each retains authority over its own resources and responsibilities.

Span of control

The number of subordinates reporting to one supervisor; ICS targets five, with an acceptable range of three to seven.

Safety officer authority

The safety officer monitors operations and may halt activities that present imminent danger, independent of the incident commander.

Nerve agent mechanism

Nerve agents such as sarin and VX inhibit acetylcholinesterase, causing acetylcholine buildup and cholinergic crisis; treated with atropine and pralidoxime.

Blister agent effects

Mustard and similar agents cause delayed skin blistering and tissue damage; symptoms may not appear for hours after exposure.

Cyanide antidote

Hydroxocobalamin or sodium thiosulfate is used for cyanide poisoning, which blocks cellular respiration; supportive oxygenation is also required.

Illicit drug lab hazards

Clandestine labs present flammable solvents, toxic gases, and explosion hazards; entry requires PPE and coordination with law enforcement.

Rescue versus recovery

Rescue targets a viable victim with a chance of survival; recovery is the deliberate retrieval of a deceased victim after hazards are controlled.

Termination activities

Post-incident tasks including debrief, critique, documentation, equipment decontamination and restocking, and after-action reporting.