Omega Engineering CYD201 and CYD208 manual Handling Cryogenic Storage Dewars

OMEGA Model CYD201/CYD208 User’s Manual

1.2HANDLING 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 (LN2) 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 LN2.

1.2.1Handling 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.

1.2.2LHe and LN2 Safety Precautions

Transfer LHe and LN2 and operate storage dewar controls in accordance with manufacturer/supplier instructions. During transfer, follow all safety precautions written on the storage dewar and recommended by the manufacturer.

WARNING

NON-

MAGNETIC

LIQUID NON-

FLAMMABLE

HELIUM

KEEP

UPRIGHT

Figure 1-1. Typical Cryogenic Dewar

•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 1-3