Twining is proud to participate in National Safety Stand Down Week. We have a unique niche in our industry as engineers, scientists, and inspectors. Although we are not builders, we work side by side with contractors on active construction sites across the state of California. This is why I have chosen to review the topic of fall protection in honor of Safety Stand Down Week.
Falls are the number one cause of fatalities in the construction industry so it definitely warrants a discussion. A person does not necessarily have to fall from great heights or off of the top of a building to be seriously injured or killed. Fatal falls can occur from a ladder, a scaffold, stairs, structural steel, an elevated work platform, through an opening in a floor or roof, or through a fragile roof surface.
So what are some ways to prevent these types of accidents? First we must consider training. No one should work at heights without thorough and on-going fall protection training. The training should take place before a person ever works at heights. The training should be task specific and address all aspects of fall protection including, but not limited to, personal fall arrest system or PFAS, guardrails, safety nets, and safe edge zone guarded by a watchman.
There are several types of PFAS designed for the many various scenarios found in construction. At a minimum, each system should include a body harness, a lanyard, an anchorage point, and a rescue plan. Most harnesses are made of very strong webbing designed to reduce the forces of a fall on the human body. In order to allow the harness to do its job as designed, it must be custom and fitted to each individual. In the United States the integral D-ring in which you attach your lanyard must be worn on the back between the shoulder blades. Special care must be taken for storage while the harness is not in use. It should be kept out of direct sunlight as the sun’s rays can weaken the fibers that comprise the harness over time. It should be kept clean and never marked on with a marker or paints. The harness should be inspected daily prior to work to check for defects, properly working hooks and buckles, or possible wear on the webbing. In addition to a daily inspection by the user, a formal documented inspection should take place bi-annually at a minimum, by a manager or supervisor. Any equipment found with problems must be removed from service immediately and destroyed.
In addition to reviewing the equipment itself, PFAS trainers should be sure each person working at heights understands how to calculate fall distance to ensure the PFAS will stop your fall before you strike a lower level or the ground. Factors in this calculation include the length of the lanyard, location of the tie-off point, and the height of the person wearing the equipment. Some lanyards are made of stitched webbing that slows your fall as the stiches break from the force of the fall. Others types, such as a self-retracting lifeline (SRL), act much like a seat belt in a car stopping your fall quickly by locking up.
A well-fitting and properly working harness and lanyard system are not sufficient if they are not attached to a proper anchorage point. Each anchorage point much be engineered to withstand 5,000 pounds of force without failure. Tying off to a stand pipe or some other non-approved anchorage point may not save you in the event of a fall. Ideally, each person will tie off over their head if possible. By raising the anchorage point over the wearer’s head, the person has that additional amount of feet to slow his or her fall and come to a stop before striking the lower level as opposed to tying off at foot level.
Finally, if a fall does occur and striking a lower level was prevented, the wearer will find himself or herself hanging suspended from their PFAS and will need immediate rescue. Make sure your job site has a written and well thought out rescue plan in the event of a fall. The rescue plan should not simply rely on calling 911. Of course 911 should be called immediately in the event of a fall, but emergency responders may take a while to get there and as the person hangs there, a condition known as suspension trauma can set in. Suspension trauma is a condition where too much blood gets trapped in the legs providing limited oxygen to the brain and vital organs. Special care must be taken with a person who was caught by his or her PFAS and rescued. Recent research is indicating that a recovered person should be placed in a completely horizontal position to aid in recovery while receiving or waiting to receive medical attention.