Cryogenic safety in helium cryostats at CERN

[摘要] Cryostats contain large cold surfaces, cryogenic fluids, and sometimes large stored energy (e.g. energized magnets), with the potential risk of sudden liberation of energy through thermodynamic transformations of the fluids, which can be uncontrolled and lead to a dangerous increase of pressure inside the cryostat envelopes. The consequence, in the case of a rupture of the envelopes, may be serious for personnel (injuries from deflagration, burns, and oxygen deficiency hazard) as well as for the equipment. Performing a thorough risk analysis is an essential step to identify and understand risk hazards that may cause a pressure increase and in order to assess consequences, define mitigation actions, and design adequate safety relief devices to limit pressure accordingly. Lessons learnt from real cases are essential for improving safety awareness for future projects. We cover in this paper our experience on cryostats at CERN and the design-for-safety rules in place.

[发布机构] Technology Department, CERN, Geneva 23; CH-1211, Switzerland^1

[效力级别] 物理学 [学科分类] 材料科学（综合）

[关键词] Cryogenic fluids;Design for safety;Limit pressures;Oxygen deficiency;Potential risks;Pressure increase;Safety awareness;Thermodynamic transformations