LIQUID NITROGEN LN2 a cryogenic liquid

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LIQUID NITROGEN (LN2)a cryogenic liquid
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Liquid Nitrogen - Risk

• A measure of the likelihood that harm from a
  particular hazard is realised the severity of the
  consequences
• Risk is situation specific, i.e. depends on
  application, quantity and frequency of use.
• Local risk assessment to identify risks and put
  in place measures to minimise them

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Liquid Nitrogen - Hazard

• The potential of an agent to cause harm to
  persons or property. For Liquid Nitrogen the main
  hazards are
• Extreme cold
• Asphyxiation
• High pressure

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Liquid Nitrogen - Extreme cold

• Liquid nitrogen 77 K (-196oC)
• Avoid direct contact with cryogen and objects at
  low temperature, e g pipes carrying the liquid
• Wear eye protection
• Wear loose fitting gloves
• Wear overalls covering top of boots to ensure
  spilt cryogens do not run inside.
• Prevent spillage

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Liquid Nitrogen - Asphyxiation

• Oxygen displacement
• Volume expansion rate 696
• (i.e. 1 m3 of LN2 will expand to 696 m3 of
  gaseous N2 at 21oC).
• Boiling at -196oC LN2 can displace 02 from the
  air and rapidly create an oxygen depleted
  environment.
• LN2 DOES NOT SUPPORT LIFE!

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Liquid Nitrogen - Asphyxiation

• Oxygen
• 21 Normal Level
• lt19 Danger Level
• lt14 Risk of permanent effects and death
• There is no sensation of breathlessness to
  warn you that you are being asphyxiated

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Liquid Nitrogen First Aid

• Cold burns
• Treat as a normal burn' hold under tepid running
  water (not hot water!) for at least 15 minutes.
  Seek medical assistance.
• Eye Contact
• Flush with water while summoning immediate help.

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Liquid Nitrogen First Aid

• Asphyxiation
• Seek immediate assistance

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LIQUID NITROGEN (LN2)a cryogenic liquid