2.2.1 - Liquid nitrogen
Never store liquid nitrogen in a sealed container. High pressures will build up and may lead to explosive rupturing of the vessel.
It must not be possible to seal any vessels used to store liquid nitrogen (LN2). All vessels that are suitable for LN2 use should be labelled accordingly. All other vessels should be removed from the area to avoid accidental use.
2.2.2 - Ethane
chameleon is designed such that:
- No source of ignition is present in any zones capable of receiving an explosive mix of air/ethane.
- An explosive mixture cannot occur during normal use. This is achieved through the combination of very low ethane boil-off rates and the presence of a protective layer of cold N2 gas over the cryogen bowl, which displaces oxygen and prevents the formation of explosive gas mixtures.
You must always follow this standard operating procedure: remove the cryogen bowl from the instrument and place it in a safe location (e.g. a fume hood) while ethane is boiling off following use.
You will need to condense liquid ethane for use on chameleon from a gas bottle or laboratory supply. Be aware that these sources could leak and produce an explosive atmosphere in the room.
Bottled ethane contains gas under high pressure which may explode if heated.
You must carry out your own risk assessment before you carry out this activity, and consider these hazards.