By Bob Whitfield, CSHM, CSMP
Harness selection is critical when it comes to building your personal fall protection system. With over 350 different styles of harnesses currently on the market, EHS professionals and end users should spend more than a few minutes ensuring they select the safest, most appropriate harnesses for the tasks at hand.
When it comes to fall protection, the phrase “just grab any harness” should not be at the top of anyone's instructions.
Early fall protection was the rope around the waist (or nothing). Then the simple safety belt came on the scene. As the science of fall protection matured, we learned that safety belts posed opportunities for serious injury during a fall.
With the birth of the full-body harness, users were given a better chance to survive the forces encountered during a fall, as the harness helped absorb and distribute the force of the fall to protect the employee from injury.
This graphic illustrates fall forces and possible injuries that could occur:
In a 2012 study, forensic pathologist William A. Cox shared the results of his study of post-fall damage to the human body. Let’s look at what that abrupt stop could do to the worker.
- Human skull – A human skull with brain weighs in at approximately 8-10 lbs. Neck and cervical injury (Whiplash & “bell ringing”) can occur.
- Lungs – With the lungs being less dense, they may separate from the chest wall tissues (Low-impact injury).
- Heart - Violent compression of the heart between the anterior chest wall and the vertebral column may occur. Cardiac injury occurs in approximately 50% of deceleration injuries.
- Ribs - Rib fractures may occur when their elastic limits are exceeded.
- Rotation - Rotational forces may substantially add to injuries. Twisting and distortion of the heart’s aorta and major veins to internal organs may occur.
The sad part with many of these fall-induced critical injuries is that they may not be identified until much later, when the worker is rushed to the emergency room with previously unrecognized complications. This is why it is so important to have a worker who has experienced a fall-related suspension to be seen immediately by a trained medical practitioner.
A comprehensive work up and blood draw should be performed. Why take a blood sample? An elevated white count could expose internal bleeding and injuries (trauma) that are not readily apparent.
This is why it is so important to select the correct harness and adjust it properly. The daily role of the pelvis is to transfer weight from the upper skeleton to the lower components of the skeleton, especially during movement. The correct harness, properly adjusted, will transmit a large portion of these fall forces down to your hips (part of your pelvic girdle). A properly designed and fitted harness is critical.
So let’s start the process of selecting the correct harness. Here are some simple questions that lead to complex answers.
What task will the end-user perform?
User tasking helps determine what characteristics and accessories the harness must have. At my current organization, I have painters, welders, horticulturalist, plumbers, electricians, carpenters, roofers, inspectors, confined space entrants, artists, cosmetologists, rope access technicians, acrobats, pyrotechnic technicians, tasks performed over water, safety professionals and an occasional flying fairy. Each one of these occupations require a different fall protection harness. Each of these users must also be aware of that particular harness’s protective features and its limitations.
What weight is the worker?
Current ANSI Z359 Standard limits user’s weight range from 130-310 lbs. In the absence of updated ANSI standards or OSHA direction that provides guidance on the selection of fall protection equipment for users below 130 pounds or over 310 pounds, industry-accepted standards (CSA, EU, AS/NZS, etc.) should be considered to determine appropriate fall protection equipment - i.e. full-body harness, connecting device, etc.- for users within these weight ranges. Many of the well-known fall protection equipment manufacturers can now provide harness selection guidance for users under 130lbs. and over 310 lbs.
What gender is the worker?
As we all learned in school, male and female anatomies differ in many ways. When considering a harness, remember that most universal harnesses may hit the female build too high on the hips and may not be able to adjust at the chest properly to provide sufficient protection in a fall. A number of manufactures now have harnesses designed specifically for women.
What height is the worker?
Many manufacturers build for the average person (50th percentile male/female), who is approximately 5'6", with an elbow height of 42" and a waist height of 40". Larger males/females (95th percentile) are approximately 6'0" with an elbow height of 46" and a waist height of 45". I personally take an X-Large Tall harness. My mom use to say I was “husky” when buying pants. I’m in the 98+ percentile human category that is hard to fit. I’m well over six feet tall and over 275 pounds.
Life-changing and life-saving
As you can clearly see, humans are not designed to fall. Our bodies don’t react well to sudden stops.
Let’s look at a gymnast, they traditionally start out training on a balance beam that is actually resting on the floor and as they gain skill, balance and strength that bar is slowly raised. Each time they perform a summersault, flip, leap or vault they create micro tears within supportive muscle groups. The body reacts, heals these areas and builds additional muscle to further support these critical areas. The end result is that the trained gymnast can perform at a greater height and “stick” that all-important landing in competition with less injury.
Now look around the construction site, the warehouse or any area where workers are performing tasks at height. You won’t see many trained gymnasts. What you will see are workers who count on the correct selection of fall protection equipment for their protection and the comprehensive training to recognize its correct use and its limitations.
The selection of the correct harness, for the correct task, for the right body size and weight is critical. Don’t just grab any harness, connecting device or temporary anchorage device as you head out to perform a task at height or in a confined space. Take the time needed to ensure you have made the correct and most protective selection. Ask questions of a competent or qualified person when you’re unsure.
Finally, read the manufacturers documentation on your harness. Many are available instantly online. The end result of making the correct choice can be life-changing and quite possibly life-saving.
Bob Whitfield is team leader, safety (Fall Protection, AWP & Rope Access) for Walt Disney Parks & Resorts. He can be reached at Bob.Whitfield@disney.com.