BIOMECHANICAL FEATURES OF FIRE EVACUATION FOR INDIVIDUALS WITH BILATERAL LOWER LIMB PROSTHESES

Abstract

The article examines the biomechanical constraints of individuals with bilateral lower limb amputations during fire evacuation, driven by the full-scale war in Ukraine, which has increased the number of such individuals (over 50,000 as of 2023). The research focuses on the functional characteristics of modular and bionic prostheses (weight 3-7 kg) for transtibial and transfemoral amputations, particularly their impact on energy expenditure and movement speed. The study aims to assess energy costs and evacuation speed to inform the standardization of fire safety regulations for evacuation routes and exits. The analysis reveals that modular prostheses enable speeds of 25-50% of pre-amputation levels on horizontal surfaces (0.4-0.8 m/s) and 10-30% on stairs (0.15-0.4 m/s), while bionic prostheses achieve higher rates of 40-70% (0.7-1.2 m/s) and 20-45% (0.25-0.6 m/s), respectively. Energy expenditure increases by 5-10% per kilogram of prosthesis weight, reaching +40-60% for transtibial and +100-120% for transfemoral amputations. Graphical dependencies of energy costs on prosthesis weight and comparisons of evacuation speeds were developed, confirming the significant influence of prosthesis type and amputation level. The findings highlight the need to adapt existing evacuation time calculation methods to account for reduced speed and high fatigue (effective distance 50-100 m) in individuals with bilateral lower limb prostheses. The scientific novelty lies in the comprehensive analysis of biomechanical characteristics of bilateral prostheses in the context of evacuation, conducted for the first time in Ukraine with consideration of the war context. Quantitative indicators of speed and energy expenditure provide a basis for updating regulatory standards. The practical value of the study is in supplying data for developing inclusive evacuation strategies that address the needs of individuals with limited mobility, particularly in emergency situations.