Self-Retracting Lifeline, a type or vertical fall arrestor. Very often used in conjunction with permanent ladders or the wire-rope laders used to access lighting trusses. Works much like the inertia reel mechanism of the seatbelt in your car: free movement until it senses a jerk, then it locks up.
One manufacturer:
View attachment 6377
http://www.millerfallprotection.com...ifelines/mightylite-self-retracting-lifelines
NOT TO BE USED WITHOUT PROPER TRAINING, and no substitute for common sense.
One manufacturer:
View attachment 6377
http://www.millerfallprotection.com...ifelines/mightylite-self-retracting-lifelines
NOT TO BE USED WITHOUT PROPER TRAINING, and no substitute for common sense.