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SafetyProduct Manual - Perma-Cyl®w/ FlexFill™ Piping Option
Oxygen Enriched Atmospheres
An oxygen-enriched atmosphere occurs whenever the normal
oxygen content of air is allowed to rise above 23%. While
oxygen is nonammable, ignition of combustible materials
can occur more readily in an oxygen-rich atmosphere than
in air; and combustion proceeds at a faster rate although no
more heat is released.
It is important to locate an oxygen system in a well
ventilated location since oxygen-rich atmospheres may
collect temporarily in conned areas during the functioning
of a safety relief device or leakage from the system.
Oxygen system components, including but not limited to,
containers, valves, valve seats, lubricants, ttings, gaskets
and interconnecting equipment including hoses, shall have
adequate compatibility with oxygen under the conditions
of temperature and pressure to which the components may
be exposed in the containment and use of oxygen. Easily
ignitable materials shall be avoided unless they are parts of
equipment or systems that are approved, listed, or proven
suitable by tests or by past experience.
Compatibility involves both combustibility and ease of
ignition. Materials that burn in air may burn violently in pure
oxygen at normal pressure, and explosively in pressurized
oxygen. In addition, many materials that do not burn in
air may do so in pure oxygen, particularly when under
pressure. Metals for containers and piping must be carefully
selected, depending on service conditions. The various steels
are acceptable for many applications, but some service
conditions may call for other materials (usually copper or
its alloy) because of their greater resistance to ignition and
lower rate of combustion.
Similarly, materials that can be ignited in air have lower
ignition energies in oxygen. Many such materials may
be ignited by friction at a valve seat or stem packing, or
by adiabatic compression produced when oxygen at high
pressure is rapidly introduced into a system initially at low
pressure.
Warning! If clothing should be splashed
with liquid oxygen it will become
highly ammable and easily
ignited while concentrated
oxygen remains. Such clothing
must be aired out immediately,
removing the clothing if possible,
and should not be considered
safe for at least 30 minutes.
Nitrogen and Argon
Nitrogen and argon (inert gases) are simple asphyxiates.
Neither gas will support or sustain life and can produce
immediate hazardous conditions through the displacement
of oxygen. Under high pressure these gases may produce
narcosis even though an adequate oxygen supply sufcient
for life is present.
Nitrogen and argon vapors in air dilute the concentration
of oxygen necessary to support or sustain life. Inhalation
of high concentrations of these gases 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 or argon 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.
Personal Protective Equipment
(PPE)
The following personal protective equipment is
recommended when working around cryogenic liquid:
• Safety glasses with side shields to prevent cryogenic
liquid from splashing into the eyes
• Chemical / Liquid resistant gloves to prevent cryogenic
burns on exposed hands
• Long sleeve shirts to protect the arms
• Cufess trousers worn over closed shoes