Incident
A blockage occurred in a tall chute. The blockage went unnoticed and workers continued to introduce debris into the chute. The installers had calculated the weight of the unblocked chute to be 1500 lb. (680 kg).
Debris continued to accumulate in the chute until the blockage was finally discovered by the inattentive safety monitor. A crane was called in and the entire chute was lowered to the ground. The crane’s load indicator showed the total weight of the chute and blocked debris to be 15,000 lb. (6800 kg).
Upon inspection of the cable assemblies, no obvious signs of strain were noted. The chute sections were equipped with cable assembly pairs having a combined working load limit of 2000 lb. (900 kg). The breaking strain of the cable assembly pairs is 20,000 lb. (9000 kg).
Action
Although the cable assemblies showed no obvious sign of strain, the working load limits were greatly exceeded. All the cable assemblies should be replaced.
Conclusion
If, during the course of your job the working load limits of the cable assemblies are accidentally exceeded, consult a structural engineer and the Superchute® factory to determine whether the chute sections in that system must be refitted with new cable assemblies.