Deceleration device

FIGURE 11 Example of a solids deceleration device. Source Courtesy of GEA Process Engineering. 

A system used to arrest an individual s fall. It consists of a substantial anchorage, full body harness, and lanyard, and may include a deceleration device, lifeline, or suitable combinations of these. The components are sometimes referred to as ABCs, i.e., A for anchor point means, B for body harness, and C for connecting device (lanyards). See also ASSE Z359.1, Safety Requirements for Personal Fall Arrest Systems, Subsystems, and Components Fall Restraint System. 

Residential construction poses special concerns for contractors. One of the biggest concerns is falls, so OSHA requires fall protection that meets the residential construction requirements of 29 CFR 1926.501(b)(13). According to the regulation, residential construction employers generally must ensure that employees working six feet or more above lower levels use conventional fall protection methods, including guardrails, safety nets, or personal fall arrest systems. A personal fall arrest system may consist of a full body harness, a deceleration device, a lanyard, and an anchor point. (See the definition of personal fall arrest system at 1926.500). 

Fall restraint (Positioning device system) means a body belt or body harness used to prevent an employee from free falling more than two feet and where self rescue can be assmed. It consists of an anchorage, connectors, a body belt or harness and may include a lanyard, deceleration device, lifeline, or suitable combination of these. 

Body belt (safety belt) means a strap with means both for securing it about the waist and for attaching it to a ianyard, iifeiine, or deceleration device. 

Anchorage means a secure point of attachment for lifelines, lanyards or deceleration devices. 

Deceleration distance means the additional vertical distance a falling employee travels, excluding lifeline elongation and free fall distance, before stopping, from the point at which the deceleration device begins to operate. It is measured as the distance between the location of an employee s body belt or body harness attachment point at the moment of activation (at the onset of fall arrest forces) of the decelera-... 

Free fall distance means the vertical displacement of the fall arrest attachment point on the employee s body belt or body harness between onset of the fall and just before the system begins to apply force to arrest the fall. This distance excludes deceleration distance, and lifeline/lanyard elongation, but includes any deceleration device slide distance or self-retracting lifeline/lanyard extension before they operate and fall arrest forces occur. 

Lanyard means a flexible line of rope, wire rope, or strap which generally has a connector at each end for connecting the body belt or body harness to a deceleration device, lifeline, or anchorage. 

Rope grab means a deceleration device which travels on a lifeline and automatically, by friction, engages the lifeline and locks so as to arrest the fall of an employee. A rope grab usually employs the principle of inertial locking, cam/level locking, or both. 

Self-retracting lifeline/lanyard means a deceleration device containing a drum-wound... 

For deceleration device systems with integrai iife-iines or lanyards which automaticaiiy iimit free faii distance to 2 feet (0.61 m) or less, the test weight shouid be rigged to free fall a distance of 4 feet (1.22 m). 

B) For deceleration device systems with integral lifelines or lanyards which automatically limit free fall distance to 2 feet (0.61 m) or less, the test weight should free fall a distance equal to that permitted by the system in normal use. (For example, to test a system with a self-retracting lifeline or lanyard, the test weight should be supported and the system allowed to retract the lifeline or lanyard as it would in normal use. The test weight would then be released and the force and deceleration distance measured). 

Rope-grab-type deceleration devices, (i) Devices should be moved on a lifeline 1,000 times over the same length of line a distance of not less than 1 foot (30.5 cm), and the mechanism should lock each time. 

Other self-activating-type deceleration devices. The locking mechanisms of other self-activating-type deceleration devices designed for more than one arrest should lock each of 1,000 times as they would in normal service. 

The deceleration distance measured for deceleration devices during the force test ... 

The ANSI A10.14—1991 American National Standard for Construction and Demolition Operations—Requirements for Safety Belts, Harnesses, Lanyards and Lifelines for Construction and Demolition Use, states that the anchor point of a lanyard or deceleration device should, if possible, be located above the wearer s belt or harness attachment. ANSI A10.14 also states that a suitable anchorage point is one which is located as high as possible to prevent contact with an obstruction below should the worker fall. Most manufacturers also warn in the user s handbook that the safety block/retractable lifeline must be positioned above the D-ring (above the work space of the intended user) and OSHA recommends that fall arrest and restraint equipment be used in accordance with the manufacturer s instructions. 

Q. Under the requirements in Part 1926 Subpart M, may one lanyard (which does not have an integral deceleration device) be attached to another lanyard (which does have an integral deceleration device), using locking snaphooks, provided that the free fall distance would not exceed six feet ... 

A secure point of attachment of lifelines, lanyards, or deceleration devices. Anchor points must be capable of supporting a static load of 5,000 pounds or 2,333 kg per person attached. 

Harnesses have straps around the thighs, waist, chest and shoulders to more evenly distribute the force of a fall and cradle the worker. Harnesses are the safer choice a harness can be used in a variety of situations and a harness can do everything a belt can do. A personal fall-arrest system should consist of an anchorage, connectors and body harness, lanyard, deceleration device, lifeline, or suitable combination of these items, according to OSHA. 

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