NORMATIVE FRAMEWORKS AND INTERNATIONAL EVIDENCE ON OCCUPATIONAL WORK UNDER HYPOBARIC HYPOXIA IN HIGH-ALTITUDE

Occupational work in high-altitude environments presents a complex array of physiological challenges and health risks due to chronic exposure to hypobaric hypoxia. Prolonged or intermittent stays at altitudes above 2,500 meters place workers at risk of acute mountain sickness, sleep and cognitive disturbances, cardiovascular stress, and long-term complications, including chronic mountain sickness and pulmonary hypertension. Despite shared physiological risks, normative regulatory acts remain heterogeneous across countries and often lag behind contemporary scientific evidence. This variability creates gaps in worker protection, complicates cross-border operations, and hampers surveillance.

Objective. To conduct a comparative analysis of the NLAs of Russia, Kazakhstan, and Kyrgyzstan regulating medical examinations of workers in high-altitude environments, and to assess their concordance with international guidelines and recent evidence.

Materials and Methods. This comparative analysis was conducted through a comprehensive review of national and international normative frameworks, alongside scientific literature and clinical guidelines related to occupational work under hypobaric hypoxia in high-altitude environments. 

Results. The analysis revealed discrepancies between formal lists of contraindications in NLAs and the current evidence based on work under conditions of hypobaric hypoxia. Russia explicitly lists hypobaric hypoxia as a harmful factor but provides general contraindications. Kazakhstan omits hypobaria, while Kyrgyzstan recognizes reduced atmospheric pressure but includes nonspecific contraindications such as hemorrhoids and hernias. International evidence emphasizes cardiovascular, respiratory, hematological, neurological, and ophthalmological risks, while conditions like hemorrhoids lack evidence-based justification.

Conclusion. It is advisable to update the NLAs by highlighting hypobaria as a separate factor and specifying contraindications based on international clinical guidelines. Harmonization with international clinical guidelines (Wilderness Medical Society, ESC, BTS) is necessary to ensure safety and avoid both over-restriction and under-protection.

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