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Science, Technology and Engineering |
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Department of Biochemistry LIQUID NITROGEN GeneralA colourless, non-flammable and odourless liquid with a boiling point at -195.8°C. (Class 2.2) Hazards Cold burn: Metals and liquids below -20°C can cause ‘burns’ with pain, blistering, tissue loss and shock. Do not grasp cold metal surfaces. Never touch liquid N2 or objects frozen with liquid N2. Suffocation: Liquid Nitrogen rapidly evaporates to form a simple asphyxiant. Ensure adequate ventilation. Open windows and doors where appropriate. Glass Dewar vessels: Glass Dewar vessels should not be used due to risk of implosion. Only steel Dewar vessels should be used. Eye injury: Liquid Nitrogen can spatter (possibly in eyes) while being poured. Flying chunks of frozen objects could cause eye injury. Risk Control Measures Only use Liquid Nitrogen after receiving safety training (Laboratory Induction & Authorisation). • Low temperature insulation is required for liquid storage and transfer. Only transfer liquid in approved vessels eg. stainless steel Dewar with the proper lid. • Wear face shield, safety shoes and use insulated protective gloves when decanting liquid nitrogen from the main storage cylinder. • When working from portable vessels, wear safety glasses and protective insulated gloves. • You must be authorised by your laboratory supervisor or senior lab member before using liquid nitrogen. First Aid Cold burn: Irrigate with tap or tepid water for 15-30 minutes Apply sterile dressing and treat as a thermal burn Seek medical attention Suffocation: Remove from exposure Check there is no obstruction of the airway if breathing is weak or has ceased Keep warm and rested Seek medical attention Spill Control Procedures Release of liquid to atmosphere will generate vapour fog clouds which can travel considerable distances. These clouds should be treated as asphyxiating atmosphere as the evaporating liquid will have replaced the air. In an emergency, allow liquid and gas to escape to atmosphere ie. ventilate the area. Applicable Standards and Regulations Australian Standard AS 1894 (Code of practice for the safe handling of cryogenic fluids). Content Approved by: Head of School |