Accidents with cryogenic fluids and what can we learn from them

Safety should be a primary consideration in any process but can be even more important when handling cryogens. Fortunately, the cryogenic industry has an excellent safety record. However, as the use of cryogenic fluids becomes more wide-spread and quantities increase, safety becomes even more important. There are several ways to learn something about how to design, build and operate cryogenic systems safely. First, we can study the properties of the fluids and the materials to be used and apply this knowledge to the system at hand. Sometimes, experiments can be performed to answer further questions. A third way to is learn from accidents. When an accident does occur, every effort should be made to learn as much as possible about the cause and see that the knowledge so obtained is available to anyone that can benefit from it. The author does not pretend to know about all the accidents that have occurred and therefore will only discuss several accidents, about which he has some personal knowledge. These accidents involve the most common cryogens, helium, hydrogen, nitrogen, and oxygen. From an investigation of these accidents some conclusions can be drawn, and suggestions can be made as to what can be done to promote greater safety in the future.