Safety Study on Load-Limiting Device for Rope Rescue

  • San-Ping Ho
  • Hue-Pei Chang
  • Chin-Feng ChenEmail author
  • Steven Chiang
  • Wei-Chih Fang
  • W. K. Chow
Conference paper


This paper provides tests on Tandem Prusik, and two mechanical devices as load-limiting device. The test results on a 3-wrap Prusik demonstrated that it would eventually break when overloaded, which contradicts to popular traditional belief that it will not continuously hold and substantially slip on rope if overloaded. The same tests conducted on mechanical devices show results of a positive maximum static slip of about 600 kgf, above which the rope will substantially slip to maintain the tension force even with further pulling above this limit. This novel finding is critical as it provides sound indication that the device would automatically make adjustments for the tension to be kept safe in the safe zone in field operations.


Prusik Overloaded Static slip Substantially slip 


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Copyright information

© Springer Nature Singapore Pte Ltd. 2020

Authors and Affiliations

  • San-Ping Ho
    • 1
  • Hue-Pei Chang
    • 1
  • Chin-Feng Chen
    • 2
    Email author
  • Steven Chiang
    • 3
  • Wei-Chih Fang
    • 4
  • W. K. Chow
    • 5
  1. 1.Department of Occupational Safety and HealthChang Jung Christian UniversityTainan CityTaiwan, ROC
  2. 2.Occupational Safety, Health and Medicine Research CenterChang Jung Christian UniversityTainan CityTaiwan, ROC
  3. 3.TRIS (SAFETY) Pte. Ltd.SingaporeSingapore
  4. 4.Fire DepartmentNew Taipei City GovernmentNew Taipei CityTaiwan, ROC
  5. 5.Department of Building Services EngineeringThe Hong Kong Polytechnic UniversityHong KongHong Kong, China

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