Handling of Cryogenic Material

UNB Reference Number: 7813
Authorized by: J. M. Anderson, President,
Effective Date: December 1, 1978
Revised: September 2001
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Intent

To outline the hazards and regulations associated with the handling of cryogenic material (i.e. generally liquified gases at low temperature).

Scope

All persons working on cryogenic systems.

Hazards

The principal hazard in the use of liquified gases is from extreme cold, where contact with the skin may cause burns similar to those from extreme heat. The dangers of asphyxiation or explosion if large quantities of gas are produced should not, however, be ignored.

Procedures

  • Personal protection, e.g., face shields, lab coats, closed footwear shall be used by all persons handling liquified gases. Such work may only be carried out in ventilated areas.
  • Open containers of liquified gas shall not be transported as spillage may cause injury.
  • Containers for liquified gases may be stoppered only with the plugs supplied by the manufacturer, thereby allowing relief of pressure buildup.
  • Contact of moisture with cryogenic containers and equipment should be avoided, as the ice formed may block openings or valves required for pressure release.
  • If insulation is required for handling cold parts of a system, e.g., when dispensing liquified gas, a "pot-holder" should be used, since cold liquid may spill into a glove and cause severe injury.
  • Use only containers specifically designed for holding liquified gases (N.B. Occupational Health & Safety Act & Regulations).
  • When transferring liquified gases from one container to another always use the proper transfer equipment.
  • Always handle liquified gases in well ventilated areas to prevent excessive concentrations of the gas from accumulating in the air.
  • Extra precautions are required for handling liquid oxygen to prevent fire hazards. These include no smoking in the area and avoiding contact of organic materials with the liquid oxygen.