OUTSERTS--Clear plastic outserts that fit over the
NEGATIVE PRESSURE--A pressure less than
mask lens. They protect the lens from scratches
atmospheric pressure. Gases and liquids flow from
when they are stored in the carrier, and they protect
higher pressure to lower pressure areas; air is drawn
the lens from chemical agent droplets, oil, and other
into an area of negative pressure.
petroleum products when the mask is worn.
NERVE AGENTS--These agents radically disturb the
OV E R H AU L -- A n e x a m i n a t i o n a n d c l e a n u p
chemical processes of the nervous system, which
operation. It includes finding and extinguishing
impairs or stops other bodily functions.
hidden fire and hot embers and determining
NEUTRON--A subatomic particle that is electrically
whether the fire has extended to other parts of the
neutral.
ship.
NIOSHIMSHA--National Institute of Occupational
OXIDIZING MATERIAL--A chemical compound
Safety and Health/Mine Safety Health
that spontaneously releases oxygen at normal
Administration.
temperature and air pressure or under slight
NONPERSISTENT AGENT--A chemical agent that
when released, dissipates or loses its ability to cause
OXYGEN--The content of the surrounding air.
casualties after a few minutes.
Ordinarily, a minimum concentration of 15%
oxygen in the air is needed to support flaming
NOZZLEMAN--The nozzleman mans the attack hose
nozzle so that the fire may be extinguished.
OXYGEN BREATHING APPARATUS (OBA)--An
NUCLEAR BURSTS--An explosion resulting from a
entirely self-contained breathing apparatus. It
fission or fusion reaction.
enables the wearer to breathe independently of the
NUCLEAR RADIATION--The four types of nuclear
outside atmosphere. It produces its own oxygen from
radiation released as the result of a nuclear
chemical reaction and allows the wearer to enter
explosion are alpha particles, beta particles, gamma
compartments, voids, or tanks that contain smoke,
rays, and neutrons.
dust, or fire, or those that have a low oxygen content.
NUCLEAR RADIATION INJURY--Unlike injuries
OXYGEN INDICATOR--Measures atmospheric
concentrations of oxygen over a range of 0-25%.
from other weapon effects, nuclear ionizing
Typical application is to check for potential
radiation injuries may not become evident
oxygen-deficient atmospheres during post fire
immediately unless a high enough dose is received.
operations.
Nuclear radiation, even in very small doses, has
some harmful effects on the body.
OXYGEN-DEFICIENT ATMOSPHERE--Any
oxygen concentration less than 19.5% at normal
NUCLEUS--The central region of an atom, composed
atmospheric pressure.
of protons and neutrons.
OXYGEN-ENRICHED ATMOSPHERE--Any
O D O R T H R E S H O L D L I M I T -- T h e l ow e s t
oxygen concentration greater than 22% by volume
concentration of a contaminant in the air that
at normal atmospheric pressure.
produces a scent that humans can smell.
PARTICULATE MATTER--Solid contamination
ON-SCENE LEADER--The on-scene leader is the
appearing as dust, powder, grains, flakes, fiber, or
person in charge at the scene.
stains, usually removable by settling, filtration, or
ON-STATION MONITORING--This information is
centrifugal purification.
used in determining when fallout ceases and in
PATCHING MATERIALS--Prefabricated wooden
estimating accumulated doses at these locations.
box patches in various sizes, rags, pillows,
OSHA STANDARDS--Those standards issued by the
mattresses, blankets, kapok life jackets, metal plate,
Department of Labor's Occupational Safety and
folding metal plate patches, flexible sheet metal
Health Administration pursuant to section 6 of the
patches, prefabricated steel box patches, bucket
OSHA.
patches, and welded steel patches.
OUTGAS--To remove imbedded gas from a substance
PATHOGENS--Living organisms that include
by heating.
bacteria, viruses, rickettsias, fungi, and protozoa.
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