Fall Prevention
California's fall protection safety order states that:
"Approved personal fall arrest, personal fall restraint or positioning systems shall be worn by those employees whose work exposes them to falling in excess of 7 1/2 feet from the perimeter of a structure, unprotected sides and edges, leading edges, through shaftways and openings, sloped roof surfaces steeper than 7:12, or other sloped surfaces steeper than 40 degrees not otherwise adequately protected[...]"
When assessing the workplace for fall hazards, it is important to undertake a complete risk evaluation. This evaluation can be done in the form of a job hazard analysis, where the work task is broken down into a number of distinguishable steps. The steps are then analyzed to determine the hazards and identify preventive measures to protect against the hazards. The selection of the particular fall protection system to control the hazard to the worker is dependent upon the circumstances and the job task.
Control Measures (Fall Protection Systems)
- Surface protection (non-slip flooring)
- Fixed barriers (handrails, guardrails)
- Surface opening protection (removable covers, guardrails)
- Travel restraint systems (safety line and belt)
- Fall arrest systems (safety line and harness)
- Fall containment systems (safety nets)
Ideally, the choice of a protection system will be one that removes the risk of falling entirely. For example, it is preferable to provide a fixed barrier to prevent a worker from falling, than personal protective equipment (safety harness and lifeline). In this way, the worker is never in a position where an actual fall may occur. Otherwise, the worker must rely on the personal protective equipment system to safely arrest the fall.
Elements of Fall Protection/Arrest Systems
Personal Fall Arrest Systems (PFAS) consist of four types of necessary equipment. Choosing the right piece in each category is critical to safe functioning of the system and protection of the worker. Ensure that all pieces are compatible with each other, inspected regularly, and replaced after a fall or if they show signs of wear that could affect their performance.
Anchorage means a secure point of attachment for lifelines, lanyards or deceleration devices. "Anchorages used for attachment of personal fall arrest equipment shall be independent of any anchorage being used to support or suspend platforms and capable of supporting at least 5,000 lbs. (22 kN) per employee attached, or shall be designed, installed, and used as follows :
[OSHA 1926.502(d)(15)(i)] : As part of a complete personal fall arrest system which maintains a safety factor of at least two; and [OSHA 1926.502(d)(15)(ii)] : Under the supervision of a qualified person.
Remember that while anchorage devices may be capable of supporting the required 5,000 lbs. or greater, an anchorage device is only as good as the anchorage point to which it is attached. When choosing an anchorage point, be certain that it is appropriate for the system being attached: PFAS utilizing a standard shock absorbing lanyard as a deceleration device must be capable of supporting a 310 lb. person after free falling for 6 feet (5,000 lb. requirement). PFAS utilizing a self retracting lifeline must be capable of supporting twice the potential impact energy generated by a 310 lb. person who has fallen (3,000 lb. requirement).
Be smart - choose your anchorage point wisely !
Body Harness means straps which may be secured about the employee in a manner that will distribute the fall arrest forces over at least the thighs, pelvis, waist, chest and shoulders with means for attaching it to other components of a personal fall arrest system.
"Personal fall arrest systems , when stopping a fall, shall limit maximum arresting force on an employee to 1,800 lbs. when used with a body harness" [OSHA 1926.502(d)(16)(2)].
Please Note : Effective January 1, 1998, Belts are illegal for use as fall protection. They may, in some circumstances, be used for positioning purposes only.
Body Harnesses, or Full Body Harnesses as they are commonly referred to, are designed to protect a worker from falling while limiting the extent of potential injury resulting from a fall. In order for a Full Body Harness to accomplish this task, several factors must be considered. Perhaps most importantly, the harness should be adjusted to fit the wearer properly. A harness should be snug but comfortable, and should not bind the wearer. The sub-pelvic strap should be positioned under the buttocks; this strap and its proper placement is crucial as it is the sub-pelvic strap that dissipates much of the energy generated in a fall. All connectors must be fastened properly, the chest strap must be fastened securely, and the dorsal D-ring should rest between the wearer's shoulder blades.
Connector means a device which is used to couple (connect) parts of the personal fall arrest system and positioning device systems together. It may be an independent component of the system, such as a carabiner, or it may be an integral component of part of the system (such as a buckle or D-ring sewn into a body belt or body harness, or a snap-hook spliced or sewn to a lanyard or self-retracting lanyard).
"Connectors shall be drop forged, pressed, or formed steel, or made of equivalent materials" [OSHA 1926.502(e)(3)]. "Connecting assemblies shall have a minimum tensile strength of 5,000 lbs. (22 kN)." [OSHA 1926.502(e)(5)].
Connectors come in a wide variety of shapes and sizes and, as stated above, may be an independent part of the PFAS, or an integral part of one of the PFAS components. Connectors should be selected with respect to their potential attachment point. For example, will the connectors allow the components to fit together properly, and is there a potential for accidental disconnection. WARNING: NEVER CONNECT TWO SNAPHOOKS TO ONE ANOTHER, HOOK-TO-HOOK. Independent connectors used as attachments to anchorage points or anchorage devices should be considered along the same guidelines. The most important aspect of connectors is inspection before use. Damaged, abused, or worn out connectors will render the PFAS component useless, and it must be immediately withdrawn from service.
Decelerator or deceleration device means any mechanism, such as a rope grab, rip-stitch lanyard, specially-woven lanyard, tearing or deforming lanyard, automatic self-retracting lifeline/lanyard, etc., which serves to dissipate a substantial amount of energy during a fall arrest, or otherwise limit the energy imposed on an employee during fall arrest.
"Personal fall arrest systems, when stopping fall, shall : limit maximum arresting force on an employee to 1,800 lbs. (8 kN) when used with a body harness; be rigged such that an employee can neither free-fall more than 6 feet (1.8 m), nor contact any lower level." [OSHA 1926.502(d)(16)(iii),(iv),(v)]
Choice of a deceleration device should be determined primarily by the amount of clear free fall space below the user. All users of fall protection equipment should be competently trained in how the equipment works and how to calculate free-fall, deceleration, elongation, total fall distance, and total clearance distance. Self retracting lifelines are recommended when there is a limited fall distance to the next level or the ground. Whether the deceleration device is a shock-absorbing lanyard or a self-retracting lifeline, it is important that the anchorage point for the deceleration device be located as close to directly above the user's head as possible. Traveling more than 15º in any direction from the anchorage point increases the possibility of a "pendulum" effect wherein the user falls, and the arc of travel after complete arrest allows contact with the lower level or other obstacles to the side of a vertical trajectory. These swing impacts can injure or kill an employee who otherwise would have survived the fall unscathed.
Competent vs Qualified
A "competent person" is defined by 29 CFR 1926.32(f) as someone "...who is capable of identifying existing and predictable hazards in the surroundings or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them"
A "qualified person" is defined by 29 CFR 1926.32(m) as someone "...who , by possession of a recognized degree, certificate, or professional standing, or who by extensive knowledge, training, and experience, has successfully demonstrated his ability to solve or resolve problems relating to the subject matter, work, or the project".
REMEMBER: A Competent person may NOT be Qualified !
Information Resources
Federal OSHA page on fall prevention and protection