Cryogenic compounds include liquid (liquid oxygen, liquid helium, liquid nitrogen, others) and solid (dry ice) gases.
Requirements:
(1) proper training
(2) proper personal protective equipment (PPE)
(3) proper containers
(4) proper delivery
(5) proper use
Training - Everyone coming in contact with cryogenic compounds should be educated about:
(1) the hazards of cryogenic liquids.
(2) the importance of personal protective equipment.
(3) the importance of proper cryogenic equipment and hazards of unapproved containers.
(4) the operation of cryogenic vessels and transfer devices.
Personal protective equipment should include:
(1) face visor or goggles
(2) long sleeve shirt
(3) full length cuffless pants
(4) footwear with closed toes
(5) loose fitting nonabsorbent leather gloves that can be readily removed
(6) full length apron of leather or other nonabsorbent material
Proper container:
(1) Use only approved cryogenic vessel able to withstand cold temperatures. Liquid gases with very low temperatures may require special cryogenic containers.
(2) Make sure that pressure relief valves are functioning and unobstructed.
(3) Tape all glass dewars to prevent splintering.
Proper delivery:
(1) Containers should be moved by suitable handtrucks.
(2) The containers should not be transported on public elevators.
(3) Use approved transfer devices and proper technique when transferring cryogenic material to a holding container.
Proper use:
(1) Prevent splashing and spills. Do not overfill containers.
(2) Watch for ice plugs in narrow necked containers.
(3) Work in rooms with adequate ventilation. Consider installation of an oxygen sensor in rooms where cryogenic materials are used regularly.
(4) Avoid open flame when working with a flammable gas.
(5) Use tongs to handle cryogenic solids or to add or remove material from a cryogenic liquid.
