Safety considerations with top-loading cryostats,involving ‘icing-up’ of the sample space with solid air

摘要

Safety considerations involving ‘icing-up’ with solid air of the sample space of top-loading cryostat equipment are discussed, where uncontrolled de-icing may cause a flash-to-gas, leading to trapped volumes being placed under high pressure. Methods of prevention and resolution of freeze-ups are elaborated, and a case is made for using a helium leak detector as part of sample changing and a heating wire wrapped around the sample stick for de-icing.