Safety Manual - Spms

SCHOOL OF PHYSICAL & MATHEMATICAL SCIENCES
LABORATORY SAFETY MANUAL
- Watches, rings, bracelets or other jewellery that could trap fluids against
should not be worn when handling cryogenic liquids as these could
freeze to your skin.
- Proper PPE such as gloves (provide high level of thermal protection
from direct contact with cold objects) and eye protection must be worn at
all times.
- Avoid skin contact with cryogenic liquid as it this will cause severe
frostbites/thermal burns. Prolong contact could lead to blood clots.
- Substances may become brittle upon contact with liquid nitrogen and
shatter, sending broken pieces flying.
- Use materials which are resistant to embrittlement (e.g. latex rubber
tubing).
- Liquid nitrogen and helium should not be used to cool flammable
mixtures because oxygen (present in the air) will condense on the surface
and lead to potentially explosive hazard.
- Cryogenic liquids can freeze water very rapidly. Careless use of water
can lead to heavy icing, which may block pressure relief valves.
Transportation of cryogens in cargo/ fireman Lifts
Liquid nitrogen should not be transported in the lift with accompanying
passengers. This is due to the asphyxiation risk involved when liquid N2
is transported in a confined space with inadequate ventilation. 1 litre of
liquid nitrogen will product 682L of nitrogen gas. In the event of a spill
or prolonged breakdown of the lift, the boiling off of liquid Nitrogen will
very quickly create an oxygen-deficient atmosphere that is fatal.
The following should be strictly complied with when transporting liquid
nitrogen through lifts:
COLLEGE OF SCIENCE 45