SC03 - Appendix 4
01 Mar 2012



Emergency procedures




​Before entering an incident area ensure that it is safe to do so since it is possible for an oxygen deficient environment in the vicinity of a major cryogenic accident to be present. Cold gas will displace ambient air including oxygen.

Remove victims to a known safe zone before administering first aid. Report the incident immediately by calling 3333 at DL and 2222 at RAL and Swindon and 222 at UK ATC to initiate the First Aider response. Severe cryogenic "burns" are similar to burns from fire.

Beware that liquid helium can liquefy oxygen in the air so all sources of ignition should be removed from the area.

Cryogens Accident Checklist

During Cryogenic Accident:

  • Do not rush into the area where somebody has physical collapsed through probable asphyxiation, since you are also likely to become a casualty.
  • Evacuate the area, and deploy warning signs if necessary.
  • Thoroughly ventilate the area, opening doors and windows or using active forced ventilation systems.
  • In case of Dewar rupture, evacuate area immediately.
  • Close open valves if possible.
  • Do not re-enter the area without self-contained breathing apparatus unless it is proved safe to do so. The presence of oxygen deficiency monitors will indicate the oxygen levels in the vicinity.
  • If liquid helium is present, remove direct sources of ignition because of the potential for oxygen enrichment.
  • Prevent liquid cryogens from entering drains, basements, pits or any confined space where accumulation may be dangerous.

Immediate Treatment:

  • Do not pull clothing away from burned or frozen skin.
    Warm the contact area by immersion in warm water (approximately 38°C), with body heat, or warm air.
  • Do not use an open flame or other significant heat source to warm burned or frozen skin.

NOTE: This procedure is the opposite of the procedure for a burn injury which is to rapidly cool the contact area.

  • Do not rub or massage the affected area.
  • Do not permit smoking or alcohol consumption.
  • Do not give analgesics (e.g. paracetamol, aspirin).
  • Prevent infection by cleansing with mild soap and water.

After Cryogenic Accident:

Remove injured personnel: Do not use intense heat on frozen skin; warm very slowly with warm water; resuscitate if necessary; get immediate medical help.
Ventilate the area.

Contact: Baker, Gareth (STFC,DL,CSD)