Safety aspects of whole-body cryochamber and cryosauna operation

Abstract

Interest in low temperature treatment is constantly increasing. Whole-body cryotherapy (WBC) devices are becoming available not only in medical centers but also in local gyms and spa centers. A new group of users are professional sport clubs where 3-minutes session of whole-body cryotherapy is post-training procedure to improve and speed up the recovery process. There are four different types of WBC devices available on the market and offered to commercial (non-medical) users. The American and European market is dominated by two of them: classic cryochambers and cryosaunas. Both constructions are supplied with liquid nitrogen. Low temperature inside classic cryochamber is produced by evaporating of liquid nitrogen in two or more heat exchangers. There is never a direct contact between user and cryogenic medium in any of system operation mode (closed supply system). Cryosauna is cooled down by filling with cold vapor of liquid nitrogen. Supply system is considered open because it allows for direct contact between user and cryogenic medium. Open supply system of cryosauna is primary and most questionable issue of its operational safety, particularly after tragic accident in October 2015. This paper presents the comparative analysis of classic cryochamber and cryosauna from safety point of view. Both devices have been analyzes and tested on existing systems in operation. Paper gives detailed analysis of constructions, supply systems and working parameters. Special attention has been focused to problem of oxygen deficiency hazard. Different failure or accident scenarios have been analyzed and discussed.