The hyperbaric chamber in the Institute of Aviation Medicine was installed in 1962-1966. Its main use nowadays is hyperbaric oxygen therapy. The presence of oxygen and high pressure increase the risk of fire. In particular, American standards define accurately safety requirements. Gradually a number of preventive provisions was adopted to minimalize inflammable substances and to reduce the danger of initiation of a fire in the chamber, and a system of gas expiration outside the chamber was installed to reduce the oxygen concentrations. Its level is systematically monitored (instrument Drager Pac III) and maintained by ventilation at a value below 23 %. After a fire in 1997 in Milano it was decided to install fire extinguishing equipment. As supplier CKD Co. Energo was selected, which was able to cope with the majority of demands. The release system of extinguishing is automatic. After activation of the centre from the fire sensing element (possibly manual) the compressed air drives water into nozzles which disperse water mist. Simultaneously oxygen respiration is replaced by air and exit is started. For depths under 20 m (training of divers) the activity of the system is restricted. The chamber was also equipped with a new monitoring and communication system for immediate contact with a physician, nurse and technician, wireless Siemens Gigaset telephones are used. The fire extinguishing system was tested in practice and ensures safety of patients from effects of fire in the hyperbaric chamber.

        Key words: hyperbaric oxygen therapy, fire preventive measures, fire extinguishing, automation