This study investigates the kickback force (F_K) experienced by firefighters during fire suppression using hoses of varying diameters and different nozzle sizes. Rigorous ground tests were conducted, where a fire engine was employed to propel water through a 200 ft hose line, simulating real-life firefighting scenarios while using the hip grip and clamp techniques for hose advancement. Two distinct hose sizes, 1^3/4 and 2^1/2 in., were employed with solid stream nozzles of varying diameters, facilitating the examination of kickback forces at different attacking angles. The findings substantiate that the F_K exhibits variability in response to changes in the attacking angle when utilizing the clamp technique, which encompasses angles of 45°, 30°, and 15°. The 45° angle exhibits the lowest force, while the 30° angle manifests the highest force, demonstrating a notable discrepancy of up to 25% compared to the 45° scenario. The F_K observed at the 15° angle for the clamp technique closely approximates the corresponding values derived from the hip grip hose advancement method. The results also underscore the necessity of regarding the NFPA nozzle reaction force as an integral component of the all-encompassing F_K experienced by firefighters during hose line operations. The NFPA nozzle reaction force resulted significantly below the actual F_K observed in all tested experiments, displaying the most substantial difference of 50% in the case of the 30° angle utilizing the clamp technique.

本研究调查了消防员在使用不同直径和不同喷嘴尺寸的软管进行灭火时所经历的反冲力 (F _{K )。}进行了严格的地面测试，使用消防车将水推进 200 英尺的软管，模拟现实生活中的消防场景，同时使用臀部抓握和夹紧技术推进软管。两种不同的软管尺寸，1 ^3/4和 2 ^1/2英寸，采用不同直径的实流喷嘴，便于检查不同攻击角度的反冲力。研究结果证实，当使用夹紧技术时，F _K会随着攻角的变化而变化，其中包括 45°、30° 和 15° 的角度。45° 角表现出最低的力，而 30° 角表现出最高的力，与 45° 场景相比，存在高达 25% 的显着差异。在夹紧技术的 15° 角处观察到的F _K非常接近从髋握软管推进方法得出的相应值。结果还强调了将 NFPA 喷嘴反作用力视为消防员在软管作业期间所经历的全方位 FK 的一个组成部分的必要性_。NFPA 喷嘴反作用力明显低于所有测试实验中观察到的实际 F _K，在使用夹紧技术的 30° 角度的情况下显示出 50% 的最大差异。