P OW E R C H E C K VA LV E -- D i a p h r a g m t y p e ,
PERCUTANEOUS HAZARD--A chemical or
biological agent that can harm the skin or enter the
normally closed, seawater pressure-operated
body through unbroken skin. Also called a skin
control valve. This valve allows the flow of AFFF
hazard.
from the pump to be mixed with seawater and
protects the AFFF tank from seawater
PERIODIC TESTING--Testing conducted during
contamination or dilution.
the course of an operation at intervals greater than
15 minutes, based on the nature of the space, its
POWERTROL VALVE--Diaphragm type, normally
contents, and the nature of the operation.
closed, seawater pressure-operated control valve.
This valve allows the flow of AFFF/seawater
PERMEABLE--Having pores or small openings that
solution through the distribution system or controls
allow passage of some liquids or gases. For
seawater flow on flight deck injection systems.
example, the material from which the chemical
protective overgarment (CPO) is made is permeable
PRESSING-UP--The process of completely filling a
to water vapor.
space with liquid to displace flammable vapor/air
mixtures.
PERMISSIBLE EXPOSURE LIMIT (PEL)--The
maximum permissible concentration of a toxic
PRESSURE LOCK--A shipboard passageway with a
chemical or exposure level of a harmful physical
quick-acting watertight (QAWT) door on either
agent to which personnel may be exposed. PEL is
end. Only one door is opened at a time to prevent the
based on a time-weighted average (TWA) for a
flow of air from a pressurized part of the ship to an
normal 8-hour day, 40-hour, 7-day week.
unpressurized area. Unlike an air lock, a pressure
lock does not have air sweep fittings for purging
PESTS--The meaning of the term pest as used here is
contaminated air. Therefore, it is not used in a
restricted to certain animals (excluding
contaminated environment.
microorganisms) that interfere with the health of
other organisms. Pests are known as parasites when
PRE-WETTING--Activation of the Countermeasure
they obtain their food from living host cells.
Washdown System before the arrival of chemical
PHONE TALKER--The phone talker mans the phone
and biological contamination.
between the supervisor at their location and other
PRIMARY CIRCUITS--The number of primary
stations and receives messages from other phone
circuits used within the sound-powered battle
talkers and relays them to their supervisor.
telephone system varies among ships. The size and
PLATFORMS--Partial decks below the lowest
type of your ship normally determines the choice of
complete deck used broken to admit machinery or
circuits.
other spaces and are called platform decks or just
PROTECTION FACTOR--The reciprocal of a
platforms.
transmission (or shielding) factor. A radiation
PLUGGING MATERIALS--Plugging materials
measurement at an interior location can be
include wooden plugs and wedges and wooden
multiplied by the protection factor for that space to
shoring.
estimate the radiation level at the corresponding
exterior location. A protection factor is always
PLUGMAN--The plugman connects the hose to the
greater than one. Multiplying by a protection factor
fireplug, and when directed to do so and while the
is mathematically equivalent to dividing by a
nozzle is closed, open the fireplug valve to activate
transmission factor.
the hose.
PROTECTIVE MASK--A primary means of defense
POOP DECK--A partial deck above the main deck
against CB agents is the protective mask. The mask
located all the way aft.
is designed to protect the face, eyes, and the
P O RTA B L E S U B M E R S I B L E P U M P S -- T h e
respiratory tract of the user from tactical
portable submersible pump used aboard naval ships
concentrations of chemical and biological agents,
is a centrifugal pump driven by a water-jacketed
toxins, and radioactive fallout particles.
constant speed ac electric motor and may be
PROTECTIVE SHIELDING--A method of defense
designed to operate as single or three phase at 120,
against nuclear radiation.
240, or 440 volts.
AI-17
