Anchors and Body Support and Connectors, Oh My!

Fall protection equipment can boggle even the most educated safety director. Do you know how to specify equipment appropriate to your employees' tasks?

Fall protection equipment is not one-size-fits-all, nor is it one-product-fits-all-applications. In the construction industry, for example, equipment may need to change when anchorage points change as work progresses. This aspect can make equipment selection a challenge.

Realizing how each component of a personal fall arrest system fits into the ABCDs of fall protection, as well as the varieties of equipment that are available in each of those areas, can help safety directors specify equipment appropriate for the task. What follows is a review of the ABCDs of fall protection, and a discussion on how equipment can differ for each, using construction, utilities and confined spaces as examples.

THE ABCDS OF FALL PROTECTION EQUIPMENT

The basic components of every personal fall arrest system fall into one of the following categories:

  • A for anchorage: A secure, structural point of attachment for the fall arrest system. The anchorage connector provides a means of attaching the personal fall arrest system to the anchorage. Anchorage connectors can include beam, concrete and roof anchors; tie-back lanyards; horizontal lifeline systems; ladder safety systems; and freestanding systems, among others.

  • B for body support: A full-body harness that provides a connection point on the worker for the personal fall arrest system.

  • ANCHORAGE CONNECTOR

    C for connector: A device used to link the body support component of the system to the anchorage connector. Connectors can include self-retracting lifelines, shock-absorbing lanyards, winches, wall-form assemblies and rebar assemblies.

  • D for descent/rescue: A device used to rescue a worker post-fall arrest. This can include typical job site equipment such as lifts and ladders, or equipment designed specifically for rescue, such as pre-engineered self- or assisted-rescue devices.

Each industry uses different equipment for each element of the system, and within the industry, different applications will require different equipment. What makes equipment selection differ for each application is the presence/location of the anchorage — is it overhead, at foot level or somewhere in between; fall clearance — how much space is there between the level at which work will be performed and the ground/next lowest level; mobility — how much the worker needs to move around the job site; and miscellaneous considerations such as the type of work being performed.

In regards to miscellaneous considerations, a good example in the construction industry is welding. Hot work requires specialized equipment that is resistant to heat and flame. In the utilities industry, a special consideration would be the potential for exposure to arc flashes, which would require equipment that meets ASTM F887-05, Standard Specifications for Personal Climbing Equipment. Finally, when working in confined spaces, entry and retrieval from tight spaces with limited or unusual openings requires specialized equipment.

The construction industry has the most options for anchorage connectors due to the variety of applications. Fortunately, the anchorage usually makes it apparent what type of anchorage connector should be used. When working on a steel I-beam, such as in bridge work or steel erection, a fixed or sliding beam anchor can be used. A tie-back lanyard, which serves as both anchorage connector and connector, also may be appropriate. For work on a concrete bridge, building or ramp, a concrete anchor can be used.

A variety of roof anchors are available for commercial and residential roofing. These can be permanent or temporary, disposable or reusable, and rated for one or multiple users. On the commercial side, anchor types vary based on roofing material. An anchor that is designed for the specific type of roof — standing seam, membrane, built-up, corrugated metal, wood sheathing, etc. — should be used. Freestanding systems, such as counterweight systems, are non-penetrating anchorage points for use on flat roofs and other structures. They are pre-engineered and require virtually no installation time.

Horizontal lifelines can be used in most construction applications, including bridge work, commercial roofing, steel erection and concrete/leading edge work. Horizontal lifelines can be permanent, such as on commercial roofs, or temporary. They are used in situations where there is no appropriate overhead anchorage and a great deal of mobility is needed. Temporary horizontal lifeline stanchions can be clamped to steel I-beams, concrete rebar and shear stud and concrete loop rebar, or secured into the concrete itself.

For utility applications, anchorage connectors aren't as obvious as they are in the construction industry. Pole climbing usually involves a ladder safety system or pole anchor system. Ladder safety systems can be permanent or temporary, and within the temporary category, they can be mobile or static. Some ladder systems feature climb-assist features, in which a motorized sleeve is designed to lift weight, which, in effect, reduces the climber's weight by that amount for a faster and easier climb. A pole anchor system allows a lineman to secure an anchorage connector at the top of the pole from the ground, to which a vertical lifeline and rope grab is attached.

Some bucket trucks and aerial lifts have a built-in anchorage connector within the bucket or cage of the lift. If this is not available, a boom belt or tie-off adapter can be used to provide an anchor point on the boom.

For electrical/transformer work, base-mounted anchorage connectors such as fall arrest posts can be used for regular work at one location, and self-supporting anchorages such as hoist systems and tripods are better for work at multiple locations.

Utility plants often have a variety of fall protection scenarios that will arise during corrective and preventative maintenance, overhauls and outages. From work atop tanks and equipment, to ladders, platforms, rooftops, scaffolding and girders, each situation will require a unique solution. If the area regularly needs to be accessed, a permanent anchorage connector should be installed. Those areas with infrequent maintenance needs can utilize a temporary anchorage.

For confined spaces, there are three basic anchorages: a tripod, a hoist system and a counterweight system. Each of these systems can be used for basic confined space applications such as manhole and tank entry and retrieval when the point of entry is vertical. For more versatility, a hoist system should be used. For task-specific work such as standard manhole entry, a tripod will suit the task. A situation that requires specialized anchorage equipment is a side entry in a tank or other vessel. Equipment is available that will fit a side opening and provide a davit for lowering and retrieving personnel.

Once the anchorage connector has been selected, the hard part is over. There are far fewer options for connectors and even fewer for body support.

BODY SUPPORT

Within the body support category, there is really one piece of equipment that can be used: the full-body harness. Of course, harness features can vary dramatically from very basic, workhorse type components, to premium, high-end components for the ultimate in comfort, function and durability. Beyond the considerations of price and quality, there are task-specific functionality requirements for each application that should be considered before selecting the body support component.

In the construction industry, often a worker will wear the harness for the entire workday. To make sure this doesn't become a chore, look for a harness specifically designed for the construction industry that offers strategically located padding, as well as breathable, water-repellent and moisture-wicking materials. A belt and hip pad provide additional back support and tool carrying options, while a seat sling provides added comfort for monotonous, fatiguing tasks such as wall form and rebar work. Wall form and rebar work also will require a harness with side D-rings, as the worker will tie-off to the form using an assembly at those points.

For work requiring high visibility, such as bridge maintenance and repair, look for a harness with a built-in safety vest. Tasks such as welding and other hot work require the harness to be constructed of flame-resistant materials such as Nomex/Kevlar webbing and padding. Accessories such as hydration packs, tool bags and pouches for items such as cellular phones and safety glasses can keep productivity high.

In the utilities industry, there are two major considerations for full-body harnesses. The first is whether the work will include climbing. If so, look for a harness with a frontal attachment point for connection to the ladder system or rope grab. The second consideration is whether the task could expose the worker to an arc flash. If so, the harness must meet ASTM F887-05.

Harnesses meeting this standard must use webbing with a minimum breaking strength of 7,000 lbs, and must meet the electric arc performance criteria outlined within the standard, which means the material must not melt or drip, and must pass a drop test following exposure to the arc. Arc flash harnesses can include Nomex/Kevlar webbing and padding, a dorsal web loop instead of a metal D-ring, rescue loops for bucket truck and high-angle rescue, non-conductive and non-sparking PVC-coated hardware to reduce static buildup and leather insulators behind metal hardware to reduce static energy transfer.

Some of the non-conductive, static-reducing elements of arc-flash rated harnesses may be beneficial in confined space environments where dangerous gases can be present. Aside from this consideration, the most important factor for full-body harnesses in confined spaces is a D-ring on each shoulder. This keeps the worker on a straight plane as he or she is being lowered or raised through the opening. If only the back D-ring is used, the worker would be oriented diagonally, which can make entry and retrieval operations challenging.

Finally, don't forget that size is an important factor. A harness that is too small will be uncomfortable, discouraging compliance. A harness that is too big might not function properly, which could injure the worker. Look at the manufacturer's sizing chart to determine what size harness each worker should wear based on height and weight.

CONNECTOR

The connector usually is selected based on the anchorage connector and by analyzing how much mobility will be needed on the job site. There are two types of connectors that are used in multiple scenarios within the construction and utilities industry: shock-absorbing lanyards and self-retracting lifelines (SRL).

An SRL is a flexible lifeline attached to a mechanism that allows it to extend and retract under slight tension when the user moves away from and toward the device. SRLs typically are used when more mobility is needed. The lifeline can be made of cable, webbing or synthetic rope. Cable should be used for rugged applications or in situations where the line could contact sharp objects or edges. Webbing or synthetic rope provides a more lightweight, compact piece of equipment that can be used in many utility applications to reduce conductivity. Stainless steel offers the ultimate in corrosion resistance, reliability and longevity. The length of the lifeline varies, so look for an SRL that is long enough for the application.

Shock-absorbing lanyards include an integral shock absorber to dissipate the energy produced in a fall, limiting the forces exerted on the worker. Lanyards provide less mobility than SRLs; the length of a standard lanyard is 6 feet. Shock-absorbing stretch lanyards offer an expansion/contraction feature to avoid trips and snags; double-leg lanyards provide 100 percent fall protection while moving from one location to another; some lanyards are designed for tying off at foot level; and a tie-back lanyard wraps around a structural member and connects back onto itself, serving as both anchorage connector and connector. Lanyards often are made of webbing, but vinyl-covered cable for extra durability also is available.

Within the construction and utilities industries, the same considerations described for full-body harnesses used in welding/hot work and potential arc-flash exposure situations apply to lanyards. The material specifically should be designed for these environments and meet all appropriate standards.

Additional connectors include wall-form assemblies and chain-rebar assemblies used to connect the side D-rings on the full-body harness directly to wedge bolt slots, holes on wall forms or rebar. On a ladder-climbing system, a sleeve connects the vertical lifeline to the front D-ring on the harness.

For confined spaces, the connector typically is a winch or SRL attached to the tripod or hoist system. Winches have different style lifelines — stainless steel or galvanized — that come in different lengths, so make sure the lifeline is appropriate for the application. Winches also offer different descent speeds and other features such as a foldaway crank and revolution counter. When using a winch or SRL in raising and lowering operations, a Y-lanyard can be beneficial. This piece of equipment connects to the D-ring on each shoulder, and the two legs meet with a D-ring at the other end to connect to the winch or SRL.

DESCENT/RESCUE

For all industries, the preferred method of rescue is self-rescue, whereby the worker pulls himself back to the level from which he fell or another safe location. If this is not possible, rescue can be completed by using equipment already on the job site, such as a lift, bucket truck or ladder. No additional equipment is needed to rescue a worker who is connected to a winch or SRL with retrieval capabilities. As a last resort, pre-engineered rescue systems can be used to get the worker safely to the ground. When selecting a rescue system, look for equipment that is versatile, portable and above all, easy to use. Keep in mind the height at which work will be performed to ensure the system is capable of high-angle rescue.

In situations where response time may be slow, ensure suspension trauma straps are connected to the worker's harness. This will allow the worker to relieve pressure from the leg straps of the harness while he awaits rescue.

A recent innovation is a self-retracting lifeline with integral rescue capabilities. Prior to work, the SRL can be set to fall arrest or rescue/descent mode. In the event of a fall while in fall-arrest mode, the SRL operates like a standard SRL. If a fall occurs while in the rescue/descent mode, the SRL arrests the fall and then automatically lowers the worker safely to the ground or next level. Accessories such as rescue ladders and SRL rescue devices also are worth checking out if rescue will be a challenge at the jobsite.

All the equipment in the world won't make a difference unless workers thoroughly are trained in how to use it, and understand the consequences of not using it. It particularly is important to train and regularly refresh teams on the use of rescue equipment and procedures as the equipment is not used on a regular basis.

Fall protection equipment, with all the varieties and special features available, is not an easy thing to specify. There are many tasks that fall outside the realm of traditional construction, utility and confined space applications where equipment selection is even more difficult. The best advice in these situations is don't guess! Most equipment manufacturers are willing to consult on a special situation, as are distributors and consultants. When it comes to the lives of your employees, a safe, application-appropriate fall protection system is critical.


Craig Firl is North American technical manager with Capital Safety, a leading designer and manufacturer of fall protection and rescue products. For more information, visit http://www.capitalsafety.com or call 800-328-6146.

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