When deciding on the proper harness, it is important to determine if additional d-rings or features will be necessary to help the worker safely perform their task. For example, if a chest d-ring is required for ladder climbing, a waist belt will be needed to hold tools, etc. This section will describe the various D-rings & features that can exist on a harness and their functions:
Dorsal D-ring
The Dorsal D-ring is the primary connection point on the harness and will exist on every fall protection harness purchased. The dorsal d-ring harness is usually the only connection point on a harness rated for fall arrest, as its placement is designed to reorient the body after a fall and help the fall victim maintain the body in an upright position. When the harness is properly donned, the dorsal d-ring should be situated between the shoulder blades in the center of the back. If it's placed too high, the user runs the risk of being struck in the back of the head by the snaphook of their lanyard or self-retracting lifeline (SRL). If the dorsal d-ring is too low, the body will not be kept upright during a fall, and the user could experience further injuries during the arrest.
Side D-rings
Many workers mistakenly use side D-rings for fall arrest equipment or to park unused lanyard keepers. ANSI guidelines & product manuals will advise against both practices, so employers should be sure to review best practices & limitations when issuing equipment. Side d-rings can never be used in fall arrest applications.
The side D-rings are primarily used for work positioning, where a user is connected into a system that holds them in place and allows them to use both hands for their task instead of for balance or stabilization. Work positioning is used in many applications, but erecting rebar columns is a great example. Rebar workers will utilize a chain lanyard that connects to both side d-rings and has an oversized snaphook on the opposite end (the lanyard is "Y-shaped"). The worker can attach the snaphook directly to the rebar column so they can use both hands to continue tying rebar while their harness & lanyard keeps them in a secure position.
Side D-rings can also be used in restraint applications. Travel restraint (formerly referred to as fall restraint) is when a user is connected to a lanyard or SRL that is shorter than the distance to the nearest unprotected edge, so they are unable to fall while connected into the system. Since the user will not be subject to a fall, connecting to the side d-rings is acceptable in this application.
Front D-ring
The front D-ring's location can vary depending on the harness manufacturer. Most are placed in line with the front chest strap, while others are located near the navel area or waist level. Most chest D-rings are primarily used for ladder climbing or confined space descent. However, consult the harness manual to confirm uses and limitations. Unless otherwise stated in the harness manual, the front D-ring is not typically rated for fall arrest.
On ladder safety systems, the shuttle device that connects the user to the rail or cable system will attach to the climber's chest D-ring. In confined space applications, it is common for users to connect a winch or descent device to their chest D-ring, while the dorsal D-ring is connected to an overhead SRL.
Shoulder D-rings
Shoulder D-rings are the least common attachment method and require an additional spreader bar to operate. These d-rings are used for certain confined space descent scenarios, when a worker cannot climb down onto a ladder to access their workspace below.
Tool tether rings
On some of the newest harnesses on the market, manufacturers have included additional D-rings dedicated to tool tethers. The concept of tool tethering prevents the risk of falling objects, (AKA dropped object prevention). According to the U.S. Bureau of Labor Statistics, each year, approximately 200 occupation fatalities are caused by falling objects. Several fall protection manufacturers have expanded their offerings to provide tethers for various tools used at heights, and harnesses are now available with integrated tool anchorage points. These tool tether rings are typically located on the shoulder, side, leg straps, or on the waist belt. These D-rings can never be used for personal fall protection systems but can ensure tools dropped by a fall victim do not injure workers below.
Waist belts
A fall protection harness with an integrated waist belt is often referred to as a "construction" style harness, but it can be used for any industry. Construction workers tend to prefer waist belts so they can integrate tool belts into their fall protection harnesses. However, waist belts can also offer lumbar support and provide a more ergonomic fit for users, depending on what type of work they are performing. Anyone can use any harness. Allow subject matter knowledge to make informed equipment decisions, not vendor marketing jargon.