Liquid nitrogen presents a serious asphyxiation risk in enclosed spaces. When liquid nitrogen evaporates, it produces gaseous nitrogen, which is colourless and odourless. Nitrogen gas displaces oxygen. In a sealed or poorly ventilated room, oxygen levels can drop to dangerous levels within minutes. Loss of consciousness can occur at oxygen concentrations below about 16 percent.
For UK IVF clinics storing liquid nitrogen, the mandatory safety measures include:
Oxygen depletion monitors positioned at low level, where nitrogen gas will accumulate first. They must be calibrated and tested regularly and must trigger an audible and visual alarm at a defined threshold, typically around 19 percent oxygen.
Adequate ventilation. Rooms where significant liquid nitrogen volumes are stored should have ventilation to prevent gas accumulation. This must be assessed in your COSHH risk assessment.
Personal protective equipment. Anyone handling liquid nitrogen must wear cryogenic gloves and a face shield for any procedure involving risk of splashing. Standard rubber gloves are not adequate.
Training. All staff with any responsibility for liquid nitrogen handling must have documented training covering hazards, PPE, and emergency procedures.
Emergency evacuation procedures. Staff must know not to enter a room with a triggered oxygen alarm without breathing apparatus.
Cryolab can advise on cryogenic safety equipment for UK fertility clinic environments. Visit cryolab.co.uk“>Cryolab
