Evaluating Fire Service Escape Ropes at Elevated Temperatures and Fire Conditions

Abstract

The tools and equipment that firefighters carry on the fireground must be able to perform in the thermal conditions for which they may be deployed and utilized. Escape rope systems, which may be utilized by firefighters requiring emergency escape from an elevated position due to rapidly evolving fire conditions, are potentially life critical pieces of equipment. However, until recently traditional standardized tests required that the material properties of the rope only be evaluated at room temperature. In this study, traditional materials testing instruments were modified to quantify the capability of firefighter escape ropes to perform in the thermal conditions for which they may be deployed and utilized. These instruments have shown that at temperatures as low as 100°C, the strength of each rope was significantly reduced and at temperatures as low as 300°C, even the all aramid rope strength reduced by more than 50 %. Furthermore, this study has provided the first means of reliably and repeatably determining the available safe on-rope time. For temperature conditions comparable to those in typical structure fires, where the compartment of egress has flashed over, even the strongest ropes with the highest temperature resistance can only be expected to provide a maximum of 90 s of protection prior to failure. Pilot testing with a protective sheath concept has demonstrated a promising potential for improvement in performance.