If gas is trapped in a liquid nitrogen tank, it can cause high pressure, which means your device becomes a bomb! Plug and plug become projectile.
1) Make sure all vents are clean and regularly inspected.
2) Tie the stopper to the top of the container and use a short cord as a retainer.
3) Use check valves and pressure relief valves.
Emergency treatment method:
Accident 1 : Cold burns
method : In tepid tap water (not hot!) For at least 15 minutes.
Accident 2 : Liquid nitrogen overflows
method : Evacuation evacuation area is opened for ventilation
Accident 3 : Container overpressure
method : Evacuate area and call emergency services
Accident 4 : Asphyxia
method : Seek immediate medical attention