Full definition
A safety harness is a critical component of fall protection systems used by workers operating at elevated heights. Its primary function is to prevent injuries during a fall by effectively distributing the forces experienced throughout the body, particularly across the shoulders, thighs, and pelvis, which are the strongest skeletal areas. The design of a full-body harness includes various components: the full-body harness itself, a connecting device, and an anchorage point. The harness features a dorsal D-ring for primary fall arrest attachment, a chest D-ring for climbing ladders, and side D-rings that assist in work positioning. Each harness must allow for adjustments at the legs, chest, and shoulders to ensure a snug fit, which is crucial for effectiveness and comfort during use.
The connecting device can take several forms, such as a shock-absorbing lanyard, which limits the arrest force to less than 8 kN (1,800 lbs) in accordance with ANSI Z359.13. Alternatively, a self-retracting lifeline (SRL) can be used, which automatically manages tension and retraction, offering the fastest arrest response. Additionally, a rope grab can be utilized on a vertical lifeline, providing another layer of safety. The anchorage point must be rated to withstand a minimum of 5,000 lbs (22 kN) per OSHA requirements, or it must be capable of supporting twice the maximum arrest force as specified by ANSI standards.
Compliance with safety regulations is paramount; harnesses must be inspected before each use to check for any signs of damage, such as cuts, burns, or fraying in the webbing, as well as any deformation or corrosion in the hardware. The stitching must also be intact to ensure the harness's reliability. If a fall arrest event occurs, or if the harness reaches its manufacturer-specified life limit—typically five years from the date of first use—it must be retired from service. Training on the proper use and inspection of harnesses is also mandated by OSHA and NOM-009-STPS-2011 in Mexico, ensuring that workers are equipped with the knowledge to use this essential safety gear effectively.