The steam laboratory of the Institut de Médecine Navale du Service de Santé des Armées: a set of tools in the service of the French Navy

Accidental exposure to hot water steam is a potential risk in the French Navy, and particularly on nuclear submarines or ships. Direct human exposure to this extreme environment during an accident leads to death in a short time. In order to protect the crew members of the French Navy, a laboratory was created at the Institut de Médecine Navale du Service de Santé des Armées (IMNSSA). A set of tools was developed to study the effects of exposure to hot water steam atmospheres on human physiology and on the protective capacities of textile fabrics and equipment. A testing device allows the quantification of the protective capacities of fabrics under steam stresses. A thermal manikin and a steam climatic chamber allow the evaluation of the protective capacities of equipment. The tests on fabrics and on garments were in good agreement. Water vapour impermeable fabrics and garments provide greater protection in steamy conditions. Moreover, the thicker the sample or garment, the higher the protection it gives. Care should be taken to verify that fabrics keep their thermal characteristics under steam stress. These characteristics, measured under standard comfortable conditions, are not always indicative of the protective abilities of the fabrics under steamy conditions.