Handling Liquid Helium And Liquid Nitrogen; Handling Cryogenic Storage Dewars; Lhe And Ln; Typical Cryogenic Dewar - Omega Engineering CYD201 Operator's Manual

OMEGA Model CYD201/CYD208 User's Manual
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HANDLING LIQUID HELIUM AND LIQUID NITROGEN

Helium and Nitrogen are colorless, odorless, and tasteless gases. They
liquefy when properly cooled. Liquid helium (LHe) and liquid nitrogen (LN
may be used in conjunction with the Model CYD201 or CYD208. Although
not explosive, there are certain safety considerations in the handling of LHe
and LN .
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1.2.1

Handling Cryogenic Storage Dewars

Operate all cryogenic containers (dewars) in
accordance with manufacturer instructions. Safety
instructions are normally posted on the side of
each dewar. Keep cryogenic dewars in a well-
ventilated place, protected from the weather, and
away from heat sources. Figure 1-1 shows a

typical cryogenic dewar.

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LHe and LN

Transfer LHe and LN
controls in accordance with manufacturer/supplier
instructions. During transfer, follow all safety
precautions written on the storage dewar and
recommended by the manufacturer.
WARNING
• Liquid helium is a potential asphyxiant and can cause rapid
suffocation without warning. Store and use in an adequately
ventilated area. DO NOT vent the container in confined spaces. DO
NOT enter confined spaces where gas may be present unless area
is well-ventilated. If inhaled, remove to fresh air. If not breathing,
give artificial respiration. If breathing is difficult, give oxygen. Get
medical attention.
• Liquid helium can cause severe frostbite to exposed body parts. DO
NOT touch frosted pipes or valves. For frostbite, consult a
physician immediately. If a physician is unavailable, warm the
affected parts with water that is near body temperature.
Two essential safety aspects of handling LHe are adequate ventilation and
eye and skin protection. Although helium and nitrogen gases are non-toxic,
they are dangerous because they replace air in a normal breathing
atmosphere. Liquid helium is an even greater threat because a small
amount of liquid evaporates to create a large amount of gas. Store and
operate cryogenic dewars in open, well-ventilated areas.
Introduction
Safety Precautions
2
and operate storage dewar
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NON-
MAGNETIC
LIQUID
NON-
FLAMMABLE
HELIUM
KEEP
UPRIGHT
Figure 1-1. Typical
Cryogenic Dewar
)
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