YOUR UTILITY EQUIPMENT & TOOLING EXPERTS

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Break Load and the Safety Factors to Go With It

Safety is our number one priority and we are certain when you are on the job, that is what your top priority is as well. Safety is critical when dealing with utility construction / maintenance projects, and one of the main ways to ensure safety is by working within the load limits of crucial equipment.

What is Factor of Safety?

This factor used to ensure sufficient break load to handle working load spikes. It is critically important that all devices and tools used for pulling conductor are rated for the working loads expected on each job. Working Load (WL) is determined by the project engineer or designer.

Factor of Safety (FOS) is often notated as X to 1 or X:1

Factor of Safety is the ‘extra’ coverage of the breaking load over the working load expected. When pulling conductor or cable, many factors impact how much load your equipment must handle. Sometimes the conductor can get hung up on something which will cause the load tension to spike. The factor of safety helps accommodate a normal spike without dropping wire or experiencing equipment failure.

How do you determine Break Load?

This factor used to ensure sufficient break load to handle working load spikes.

It is critically important that all devices and tools used for pulling conductor are rated for the working loads expected on each job. Working Load (WL) is determined by the project engineer or designer.

Factor of Safety (FOS) is often notated as X to 1 or X:1

Factor of Safety is the ‘extra’ coverage of the breaking load over the working load expected. When pulling conductor or cable, many factors impact how much load your equipment must handle.
Sometimes the conductor can get hung up on something which will cause the load tension to spike. The factor of safety helps accommodate a normal spike without dropping wire or experiencing equipment failure.

How do you determine Break Load? Here is how to determine Break Load required:

Working Load requirement is set by project
Break Load must Equal or Exceed: WL X FOS (Working Load x Factor Of Safety)

To help explain this, imagine the tension for a pull is calculated to be 3,700lbs – this is Working Load of the pull. If the equipment used is only rated to a Break Load of 3,700lbs, any variation in the load tension over the standard can cause failure. So, project designers assign a factor of safety (FOS).

A FOS of 5 to 1 is commonly accepted in the US for overhead line pulls. Different countries may have a different standard.

This means that the Break Load of any tool used must be 5 times the expected load tension. In this example: Working Load of 3,700lbs x FOS of 5 = Break Load of 18,500lbs. Grips and swivels would need to be selected with a break load of 18,500lbs or more.