As used in this standard, the listed terms are defined as
follows:
(1) "Acfm": Actual cubic feet
per minute.
(2) "ASME Code or
equivalent": ASME (American Society of Mechanical Engineers) Boiler and
Pressure Vessel Code, Section VIII, or an equivalent code which the employer
can demonstrate to be equally effective.
(3) "ATA": Atmosphere absolute.
(4) "Bell": An enclosed compartment,
pressurized (closed bell) or unpressurized (open bell), which allows the diver
to be transported to and from the underwater work area and which may be used as
a temporary refuge during diving operations.
(5) "Bottom time": The total elapsed time
measured in minutes from the time when the diver leaves the surface in descent
to the time that the diver begins ascent.
(6) "Bursting pressure": The pressure at
which a pressure containment device would fail structurally.
(7) "Cylinder": A pressure vessel for the
storage of gases.
(8)
"Recompression/decompression chamber": A pressure vessel for human occupancy
such as a surface decompression chamber, closed bell, or deep diving system
used to decompress divers and to treat decompression sickness.
(9) "Decompression sickness": A condition
with a variety of symptoms which may result from gas or bubbles in the tissues
of divers after pressure reduction.
(10) "Recompression/decompression table": A
profile or set of profiles of depth-time relationships for ascent rates and
breathing mixtures to be followed after a specific depth-time exposure or
exposures.
(11) "Dive-guiding
operations": The leading of groups of trained sports divers, who use
open-circuit, semiclosed-circuit, or closed-circuit SCUBA, to local undersea
diving locations for recreational purposes.
(12) "Dive location": A surface or vessel
from which a diving operation is conducted.
(13) "Dive-location reserve breathing gas": A
supply system of air or mixed-gas (as appropriate) at the dive location which
is independent of the primary supply system and sufficient to support divers
during the planned decompression.
(14) "Dive team": Divers and support
employees involved in a diving operation, including the designated
person-in-charge.
(15) "Diver": An
employee working in water using underwater apparatus which supplies compressed
breathing gas at the ambient pressure.
(16) "Diver-carried reserve breathing gas": A
diver-carried supply of air or mixed gas (as appropriate) sufficient under
standard operating conditions to allow the diver to reach the surface, or
another source of breathing gas, or to be reached by a standby diver.
(17) "Diving mode": A type of diving
requiring specific equipment, procedures and techniques (SCUBA,
surface-supplied air, or mixed gas).
(18) "Fsw": Feet of seawater (or equivalent
static pressure head).
(19) "Heavy
gear": Diver-worn deep-sea dress including helmet, breastplate, dry suit,
weighted shoes.
(20) "Hyperbaric
conditions": Pressure conditions in excess of surface pressure.
(21) "Inwater stage": A suspended underwater
platform which supports a diver in the water.
(22) "Liveboating": The practice of
supporting a surfaced-supplied air or mixed gas diver from a vessel which is
underway.
(23) "Mixed-gas diving":
A diving mode in which the diver is supplied in the water with a breathing gas
other than air.
(24)
"No-decompression limits": The depth-time limits of the "no-decompression
limits and repetitive dive group designation table for no-decompression air
dives," U.S. Navy Diving Manual or equivalent limits which the employer can
demonstrate to be equally effective.
(25) "Psi(g)": Pounds per square inch
(gauge).
(26) "Recreational diving
instruction": The training of diving students in the use of recreational diving
procedures and the safe operation of diving equipment, including open-circuit,
semiclosed-circuit, or closed-circuit SCUBA during dives.
(27) "Scientific diving" means diving
performed solely as a necessary part of a scientific, research, or educational
activity by employees whose sole purpose for diving is to perform scientific
research tasks. Scientific diving does not include performing any tasks usually
associated with commercial diving such as: Placing or removing heavy objects
underwater; inspection of pipelines and similar objects; construction;
demolition; cutting or welding; or the use of explosives.
(28) "SCUBA diving": A diving mode
independent of surface supply in which the diver uses open circuit
self-contained underwater breathing apparatus.
(29) "Standby diver": A diver at the dive
location properly equipped and available to assist a diver in the
water.
(30) "Surface-supplied air
diving": A diving mode in which the diver in the water is supplied from the
dive location with compressed air for breathing.
(31) "Treatment table": A depth-time and
breathing gas profile designed to treat decompression sickness.
(32) "Umbilical": The composite hose bundle
between a dive location and a diver or bell, or between a diver and a bell,
which supplies the diver or bell with breathing gas, communications, power, or
heat as appropriate to the diving mode or conditions, and includes a safety
line between the diver and the dive location.
(33) "Volume tank": A pressure vessel
connected to the outlet of a compressor and used as an air reservoir.
(34) "Working pressure": The maximum pressure
to which a pressure containment device may be exposed under standard operating
conditions.