On substantiating the diameter of a rescue rope for people self-rescue in a structural fire

PURPOSE. The article describes experiments on identifying the optimal diameter of a fire rescue rope, which ensures a safe descent speed for a self-rescuing person. For a physically developed person, self-rescue in a fire does not require a specialized rescue device. It is enough to have a rescue rope and gloves that prevent burns resulting from rubbing the palms on the rope surface. METHODS. The authors carried out a static experiment to identify the optimal rescue rope diameter at which the descent speed of a self-rescuing person will be safe. Using probability theory methods and mathematical statistics, parameters of a rescue rope that can bear up a self-rescuing person are calculated. FINDINGS. The authors experimentally substantiate parameters values of a rescue rope, which an average person can use for self-rescue from height in case of fire. The identified optimal theoretical diameter of a rescue rope for self-rescue in case of fire is 23.1 mm for men and 21.2 mm for women. The closest standard diameter (i.e. the diameter produced by the industry) is 22 mm. Using rope of such a diameter, the average duration of a self-rescuing person hanging on a rescue rope is 68.4 s for men and 41.8 s for women. RESEARCH APPLICATION FIELD. The results of the study can be used when organizing self-rescue of physically developed people starting from the second floor and above in buildings of any functional purpose, including hotels, hostels, educational institutions. CONCLUSIONS. The obtained results require confirmation by dynamic tests namely by sliding of a self-rescuing person along a rescue rope of an experimentally determined diameter at a safe speed. Tests will define a safe speed and develop a method to determine the height at which each working age individual (an individual with rather strong arms) can use a rescue rope for self-rescue from the second floor and above.