CHART Cryo-Cyl80HP, Руководство по эксплуатации продукта

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Safety Product Manual - Liquid Cylinders
Safety Bulletin
Portions of the following information is extracted from
Safety Bulletin SB-2 from the Compressed Gas Association,
Inc. Additional information on oxygen, nitrogen, argon, and
cryogenics is available from the CGA
Cryogenic containers, stationary or portable, are from time
to time subjected to assorted environmental conditions of
an unforeseen nature This safety bulletin is intended to call
attention to the fact that whenever a cryogenic container
is involved in any incident whereby the container or its
safety devices are damaged, good safety practices must be
followed The same holds true whenever the integrity or
function of a container is suspected of abnormal operation.
Good safety practices dictate the contents of a damaged or
suspect container be carefully emptied as soon as possible.
Under no circumstances should a damaged container be left
with product in it for an extended period of time. Further, a
damaged or suspect container should not be refilled unless
the unit has been repaired and recertified.
Incidents which require that such practices be followed
include: highway accidents, immersion of a container in
water, exposure to extreme heat or fire, and exposure to most
adverse weather conditions (earthquake, tornadoes, etc.)
As a rule of thumb, whenever a container is suspected of
abnormal operation, or has sustained actual damage, good
safety practices must be followed.
In the event of known or suspected container vacuum
problems (even if an extraordinary circumstance such as
those noted above has not occurred), do not continue to use
the unit Continued use of a cryogenic container that has a
vacuum problem can lead to embrittlement and cracking.
Further, the carbon steel jacket could possibly rupture if the
unit is exposed to inordinate stress conditions caused by an
internal liquid leak
Prior to reusing a damaged container, the unit must be
tested, evaluated, and repaired as necessary. It is highly
recommended that any damaged container be returned to
Chart for repair and recertification.
The remainder of this safety bulletin addresses those adverse
environments that may be encountered when a cryogenic
container has been severely damaged These are oxygen
deficient atmospheres, oxygen enriched atmospheres, and
exposure to inert gases.
Oxygen Deficient Atmospheres
Warning! Nitrogen and argon vapors in air
may dilute the concentration of
oxygen necessary to support or
sustain life. Exposure to such
an oxygen deficient atmosphere
can lead to unconsciousness and
serious injury, including death.
The normal oxygen content of air is approximately 21%.
Depletion of the oxygen content in air, either by combustion
or by displacement with inert gas, is a potential hazard and
users should exercise suitable precautions.
One aspect of this possible hazard is the response of humans
when exposed to an atmosphere containing only 8 to
12% oxygen In this environment unconsciousness can be
immediate with virtually no warning
When the oxygen content of air is reduced to about 15%
to 16%, the flame of ordinary combustible materials,
including those commonly used as fuel for heat or light,
may be extinguished. Somewhat below this concentration,
an individual breathing the air is mentally incapable of
diagnosing the situation because the onset of symptoms
such as sleepiness, fatigue, lassitude, loss of coordination,
errors in judgment and confusion can be masked by a state of
“euphoria,” leaving the victim with a false sense of security
and well being
Human exposure to atmosphere containing 12% or less
oxygen leads to rapid unconsciousness. Unconsciousness can
occur so rapidly that the user is rendered essentially helpless.
This can occur if the condition is reached by an immediate
change of environment, or through the gradual depletion of
oxygen
Most individuals working in or around oxygen deficient
atmospheres rely on the “buddy system” for protection -
obviously the “buddy” is equally susceptible to asphyxiation
if he or she enters the area to assist the unconscious partner
unless equipped with a portable air supply. Best protection is
obtained by equipping all individuals with a portable supply
of respirable air. Life lines are acceptable only if the area is
essentially free of obstructions and individuals can assist one
another without constraint
If an oxygen deficient atmosphere is suspected or known to
exist:
1
Use the “buddy system.” Use more than one “buddy” if
necessary to move a fellow worker in an emergency
2
Both the worker and “buddy” should be equipped with
self-contained or airline breathing equipment.