2.3 Personal fall arrest: the A-B-C and the criteria

1 The definition, and the A-B-C

1926.500(b) defines a personal fall arrest system as a system used to arrest an employee in a fall from a working level, consisting of an anchorage, connectors, a body harness, and it may include a lanyard, deceleration device, lifeline, or suitable combinations. The same definition closes the door on the old gear: as of January 1, 1998, the use of a body belt for fall arrest is prohibited.

Everything that follows in 1926.502(d) exists to answer two questions. Will the hardware hold? And when it catches you, will the forces and distances keep you alive and reachable?

2 Hardware: connectors, D-rings and snaphooks

Paragraph (d)(6) is the most violated sentence in the whole subpart, and the violations look harmless. Choking a lanyard around a beam and clipping the snaphook back onto its own webbing. Clipping two lanyard legs into one D-ring. Hooking into an anchor eye that already has someone else's snaphook in it. Each of those creates a path for the hook to roll open under load — a failure mode called roll-out that happens at forces far below the hook's rating.

3 Lanyards, lifelines and self-retracting devices

Two consequences worth carrying. First, a horizontal lifeline is engineered equipment, not something a crew rigs between two columns — the tension in a horizontal line under load can be several times the arresting force, which is exactly why (d)(8) hands it to a qualified person. Second, the difference between (d)(12) and (d)(13) tells you why self-retracting devices matter: a device that keeps free fall under 2 feet needs less strength precisely because it generates less force, and it is the reason an SRL beats a 6-foot lanyard almost everywhere.

4 What has to happen when it catches you

1926.502(d)(16) is the heart of the standard. Personal fall arrest systems, when stopping a fall, shall:

1. 1
   (i) limit the maximum arresting force on an employee to 900 pounds when used with a body belt — a paragraph that survives only for historical reasons, since body belts have not been permitted for arrest since January 1, 1998;
2. 2
   (ii) limit the maximum arresting force on an employee to 1,800 pounds when used with a body harness;
3. 3
   (iii) be rigged such that an employee can neither free fall more than 6 feet nor contact any lower level;
4. 4
   (iv) bring an employee to a complete stop and limit the maximum deceleration distance an employee travels to 3.5 feet;
5. 5
   (v) have sufficient strength to withstand twice the potential impact energy of an employee free falling a distance of 6 feet, or the free fall distance permitted by the system, whichever is less.

Read (iii) twice. "Nor contact any lower level" is a performance requirement about the space under the worker, and it is the requirement crews most often fail while wearing everything correctly. A 6-foot shock-absorbing lanyard on a scissor lift 12 feet up satisfies the paperwork and lets a worker reach the ground. Chapter 3.2 does the arithmetic.

Note also (d)(16)(v)'s alternative in the standard's own note: an employer may use the tabulated calculations and criteria in non-mandatory Appendix C to Subpart M to demonstrate compliance with (d)(16). Appendix C is a useful document — it contains OSHA's worked guidance on system selection, clearance, anchorages and inspection — but it is guidance, not a rule.

5 Wearing it and using it

Paragraph (d)(17) settles the D-ring question for good. The dorsal D-ring — centre of the back, near shoulder level — is the fall arrest attachment. Side D-rings are for positioning. A sternal (front) D-ring is for ladder climbing systems, controlled descent or rescue, when the manufacturer rates it for that use. Clipping a shock-absorbing lanyard to a hip D-ring turns a fall into a spinal loading event and a suspension in which the worker cannot be kept upright.

Paragraph (d)(18) is the one that quietly destroys equipment. A lanyard used once to haul a bundle of conduit has taken an unknown load over an unknown edge, and nobody records it.

6 Inspection, retirement and rescue

1926.502(d)(21): personal fall arrest systems shall be inspected prior to each use for wear, damage and other deterioration, and defective components shall be removed from service. Note what the standard does not do: it gives no dimensional reject criteria — no maximum cut length, no allowable number of broken stitches. Those thresholds come from the manufacturer's instructions, and the consensus standard ANSI/ASSP Z359 addresses them in detail. Z359 is a copyrighted private standard; it is cited here by name and not reproduced.

Non-mandatory Appendix C to Subpart M, paragraph (g), publishes OSHA's own list of the conditions that take a harness or lanyard out of service — cuts, tears, abrasion, broken or pulled stitching, chemical or heat damage, distorted or cracked hardware, an activated deceleration device. Chapter 3.3 walks that list item by item.

1926.502(d)(19): personal fall arrest systems and components subjected to impact loading shall be immediately removed from service and shall not be used again for employee protection until inspected by a competent person and determined to be undamaged and suitable for reuse. In practice, treat any gear that arrested a fall as scrap: cut the webbing so nobody can put it back in the truck.

1926.502(d)(20): the employer shall provide for prompt rescue of employees in the event of a fall, or shall assure that employees are able to rescue themselves. This is a duty, not a suggestion, and it is the subject of Chapter 3.4.