Researchers from National Armed Forces of Republic of Latvia in cooperation with researchers from Technical University of Riga have started improvement program of Soldier Individual Protection System. Improvement of fire resistance was chosen as one of the program project. Using expert surveys and aprior ranking system methodology the priority body parts of soldier have been set to be protected from fire and also the main element groups of protecting systems that reference to expert assessment and mathematical treatment have to be protected from fire. Results of research may be used for further soldier’s personal protection system compliance checking for fire resistance and fire resistance system creation, focusing on prioritized sectors. Aprior ranking is a psychological experiment, when specialists (experts) have to find answer about certain factors and their effect on phenomena ranking them under effect of factor effect (weight). Aprior ranking method accomplishes in several stages. Ranked results of experts are being summarized and prepared for mathematical treatment. Ranked results and their adequacy are being checked using Spearman’s correlation coefficient, harmony of expert views is being checked by Kendel’s coefficient. Results are being interpreted by a priori ranking charts. Factors in a chart are being grouped by their effect weight so that in the next researches they may form one plan of experiment. Both cases (body parts and soldier's personal protection system for protection against fire hazards) ranks were adequate and expert views consistent. Survey showed that the most important zones to be protected from fire are head/face/neck, genitals and arms. But in Soldier’s individual protection system the main garments to soldier’s personal protection system for protection against fire hazards the main elements are helmet with pads, gloves, tactical system, CBRN gas mask with filters, military goggles. After the survey a correlation between results has obtained in Soldier's body zoning for protection against fire hazards and the results of priority group distribution of personal protection system of soldier that in addition suggests about adequate work of experts in survey