Work in hypoxic conditions--consensus statement of the Medical Commission of the Union Internationale des Associations d'Alpinisme (UIAA MedCom).

OBJECTIVES The Commission gives recommendations on how to provide health and safety for employees in different kinds of low oxygen atmospheres. So far, no recommendations exist that take into account the several factors we have outlined in this report. METHODS The health and safety recommendations of several countries were analysed for their strength and deficiencies. The scientific literature was checked (Medline, etc.) and evaluated for relevance of the topic. Typical situations of work in hypoxia were defined and their specific risks described. Specific recommendations are provided for any of these situations. RESULTS We defined four main groups with some subgroups (main risk in brackets): short exposure (pressure change), limited exposure (acute altitude disease), expatriates (chronic altitude disease), and high-altitude populations (re-entry pulmonary oedema). For healthy unacclimatized persons, an acute but limited exposure down to 13% O(2) does not cause a health risk. Employees should be advised to leave hypoxic areas for any break, if possible. Detailed advice is given for any other situation and pre-existing diseases. CONCLUSIONS If the specific risk of the respective type of hypoxia is taken into account, a pragmatic approach to provide health and safety for employees is possible. In contrast to other occupational exposures, a repeated exposure as often as possible is of benefit as it causes partial acclimatization. The consensus statement was approved by written consent in lieu of a meeting in July 2009.