What elongation figures are manufacturers required to label ropes with, according to NFPA 1983?

Manufacturers are required to label ropes with elongation figures according to specific standards outlined by the NFPA (National Fire Protection Association) in the NFPA 1983 standard. The correct figures for labeling are 300, 600, and 1000 lbf.

These figures are significant because they represent the force (measured in pounds of force) at which elongation measurements are taken. This testing ensures that users can understand how much a rope will stretch under different loads, which is crucial for safety during rescue operations. Knowing the elongation characteristics helps rescue personnel make informed decisions about the use of rope in various scenarios, as excessive elongation can affect the performance of the entire system.

Understanding the elongation data allows users to properly assess the dynamic behavior of the rope when it is loaded, which directly impacts the effectiveness and safety of rescue tactics.