UN 1977 Nitrogen, refrigerated liquid, for cooling or conditioning purposes UN Rec. 23rd rev. ed. (Shortinfo)

This gas contained in open cryogenic receptacles with a maximum capacity of 1 litre constructed with glass double walls having the space between the inner and outer wall evacuated (vacuum insulated) is not subject to these Regulations provided each receptacle is transported in an outer packaging with suitable cushioning or absorbent materials to protect it from impact damage.

Open cryogenic receptacles conforming to the requirements of P203 and containing no dangerous goods except for UN 1977, nitrogen, refrigerated liquid which is fully absorbed in a porous material are not subject to any other requirements of these Regulations.