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Safety Product Manual - CryoDoser FleX™LN2Dosing System
Caution! Before removing parts or
loosening ttings, empty the
CryoDoser FleX system of liquid
and release any vapor pressure
in a safe manner.
Safety Bulletin
Portions of the following information are extracted from
Safety Bulletin SB-2 from the Compressed Gas Association,
Inc. at www.cganet.com. Additional information on oxygen,
nitrogen, and cryogenics is available in CGA Pamphlet
P-9. Write to the Compressed Gas Association, Inc., 1235
Jefferson Davis Highway, Arlington, VA 22202..
Oxygen Decient Atmospheres
Warning! Nitrogen vapors in air may dilute
the concentration of oxygen
necessary to support or sustain
life.
The normal oxygen content of air is approximately 21%.
Depletion of 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 approximately
15 to 16%, the ame 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 decient
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 obtainable 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 decient 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.
Nitrogen
Nitrogen (an inert gas) is a simple asphyxiate. It will not
support or sustain life and can produce immediate hazardous
conditions through the displacement of oxygen. Under high
pressure this gas may produce unconsciousness even though
an adequate oxygen supply sufcient for life is present.
Nitrogen vapors in air dilute the concentration of oxygen
necessary to support or sustain life. Inhalation of high
concentrations of this gas can cause anoxia, resulting in
dizziness, nausea, vomiting, or unconsciousness and possibly
death. Individuals should be prohibited from entering areas
where the oxygen content is below 19% unless equipped
with a self-contained breathing apparatus. Unconsciousness
and death may occur with virtually no warning if the oxygen
concentration is below approximately 8%. Contact with cold
nitrogen gas or liquid can cause cryogenic (extreme low
temperature) burns and freeze body tissue.
Persons suffering from lack of oxygen should be
immediately moved to areas with normal atmospheres.
SELF-CONTAINED BREATHING APPARATUS MAY BE
REQUIRED TO PREVENT ASPHYXIATION OF RESCUE
WORKERS. Assisted respiration and supplemental oxygen
should be given if the victim is not breathing. If cryogenic
liquid or cold boil-off gas contacts worker’s skin or eyes,
the affected tissue should be ooded or soaked with tepid
water (105-115ºF or 41-46ºC). DO NOT USE HOT WATER.
Cryogenic burns that result in blistering or deeper tissue
freezing should be examined promptly by a physician.
