According to the NFPA, what tensile breaking strength should a life safety rope used for a single person load have when working with a 15-1 safety factor?

The determination of the tensile breaking strength for life safety rope when considering a single person load, with the specified 15:1 safety factor, is rooted in the standards set by the National Fire Protection Association (NFPA). According to these standards, the minimum tensile strength of a life safety rope must be sufficient to ensure the safety of an individual under load.

To understand why 4,500 lbs is the correct answer, we first consider that the generally accepted maximum load for a single person is around 300 lbs. When applying a safety factor of 15:1, the tensile breaking strength must be calculated as follows:

300 lbs (maximum load) x 15 (safety factor) = 4,500 lbs.

This calculation ensures that the rope can withstand significantly more than the maximum intended load, providing a robust safety margin for various operational scenarios that emergency responders may encounter, including dynamic loads and potential impacts during a rescue situation.

In summary, a tensile breaking strength of 4,500 lbs aligns perfectly with the requirements set forth by NFPA for life safety ropes that will be used to support the weight of one person, ensuring adequate safety measures are in place.