Improving Safety at Electrical Prefabrication Shops

These days, it's rare to meet an electrical contractor who doesn't do at least some prefabrication before heading to the jobsite. Many larger outfits run their own prefabrication shops. There are distinct advantages for contractors who operate in-house prefab teams, but there are also challenges, especially in terms of safety. Hazards in the shop environment can be quite distinct from those of an installation job site.

But when did prefab get to be such a big part of the industry? Is dependence on a prefabrication shop really more efficient than completing pulls, cuts, and bends at the job site, as they arise? Most importantly, how can contractors reduce the risk of injury while prefabricating components?

In this piece, we set out to answer these questions, with a special focus on ergonomics in the prefabrication shop.

The Rise of Prefabrication in Electrical Installations

In 2011, research group McGraw-Hill issued a SmartMarket Report about the increasing popularity of prefabrication and modularization in the construction industry. At the time, building information modeling (BIM) was an emerging force in the construction industry; the information-sharing and job-planning capabilities of BIM encourage prefabrication and modularization, and the McGraw-Hill researchers were interested in the outcome of these industrial sea changes.

Prefabrication, they found, is a winner. In their report, they polled construction industry insiders on their use of prefabrication and modularization. Their findings were overwhelmingly positive:

  • Two-thirds of the respondents said their overall project schedules were reduced by the use of prefabrication.
  • 35 percent said their prefab shops saved them four weeks or more on a construction project.
  • Nearly two-thirds — 65 percent — said that their budgets were lower thanks to the productivity gains of prefabrication.
  • 41 percent reported cost savings of at least 6 percent.
  • A majority of 77 percent said that prefabrication reduced waste at the construction site.
  • 44 percent of these reported a waste reduction of 5 percent or more.

These benefits don't come without a cost, though. Electrical contractors that venture into prefabrication need to set up what is essentially a small-scale manufacturing facility; that requires space, staff, tools and equipment. They might have to retrain field teams to work with prefab materials.

Most importantly, contractors who get serious about prefabrication and modularization will need to make plans to keep their fabrication staff safe in an environment that can be risky.

Safety Hazards in Prefabrication Shops

First off, the good news: Prefabricating electrical components may cut down on certain ergonomic risks. The Occupational Safety & Health Administration (OSHA) points out that the prefab shop makes it easier to control risk factors like work positioning, handling heavy tools, and environmental controls, including heating and air conditioning.

In fact, a well-planned fabrication shop can keep the risk of musculoskeletal injuries to an absolute minimum. The Bureau of Labor Statistics recorded 22,100 injuries among electricians in the traditional construction field in 2015. Most of those cases led to days away from work. Meanwhile, 31 percent of all nonfatal workplace injuries that year were musculoskeletal disorders, the very class of ailment that ergonomics was designed to eliminate.

Here are a few of the potentially risky tasks and movements required in the electrical prefabrication shop:

  1. Lifting heavy loads

    From large spools of wire to bundles of rigid steel conduit, many components in the electrical prefab shop weigh a great deal. When workers lift loads of more than 50 pounds, their risk of injury increases, reports OSHA.

  2. Contact stress

    Short handles on hand tools tend to press into the worker's palm. Over time, this pressure can cause pain and inflammation by restricting blood flow to the compacted tissues. Desks with sharp edges cause a similar problem when workers lean against them for long stretches.

  3. Stressful postures

    Certain bodily positions, such as bending or twisting, place stress on muscles and soft tissues. When a workstation isn't built to support a given task, workers can develop musculoskeletal injuries from these awkward postures. Even a more natural stance can cause problems when workers remain in the same position for long periods without breaks to move and stretch.

  4. Repetitive motions

    Any task can lead to strain when it's repeated over and over without variation, including the use of side cutters or crimpers. The risk of a repetitive motion injury is greater at shops that use an assembly line approach to prefabrication, unless they have staff switch stations periodically.

All of these hazards are prevalent at electric prefabrication shops, but with the right policies and equipment, every operation can reduce workplace injuries to an absolute minimum. The simplest way to remove hazards is to engineer them out — using a first-line ergonomics approach that OSHA calls "engineering controls."

The term describes changing tasks by adding material handling equipment, or by changing the worker's approach to the task, to the point where the safety hazard no longer exists. Luckily for electricians and prefab shop employees, OSHA provides plenty of tips to create engineering controls in light manufacturing environments.

Addressing the Risk: Ergonomic Strategies for Electrical Prefab Shops

The basis of all ergonomics is simple: Match the work to the worker. Through a mixture of specialized material handling equipment, repositioning of work, and strictly enforced policies, any shop can cut down on injuries and their associated costs, both human and financial.

Here are a few tips from OSHA and other safety experts on how to redesign common prefabrication tasks:

  • Handling Wire and Cable

    The first difficulty with handling wire and cable, of course, is the extreme weight of some bulk spools. Rather than attempting dangerous lifts, use a forklift equipped with a Reel Handler Attachment to transport large, heavy spools throughout the shop.

    The positioning of cable spools can also cause ergonomic risks. OSHA suggests storing commonly used spools between waist- and shoulder-height to prevent awkward postures during pulls. A Parallel Reel Payout with multiple, free-spinning reels places cable within this ergonomic power zone, with the added benefit of simplifying precuts and custom paralleling.

    Parallel Reel Payout

    Figure 1. The BHS Parallel Reel Payout is available in
    multiple reel combinations to provide the perfect wire pull.

  • Conduit Bends

    Again, weight can be an issue when dealing with large-gauge steel conduit. Only lift heavy sections of conduit manually when absolutely necessary, and then only with at least two workers.

    Even better, store lengths of conduit in raised racks and transport it with the help of a Conduit Carrier Cart. Use forklifts to transfer completed pieces where possible. For some jobs, you might even be able to palletize bent conduit for safe, easy shipment to the job site.

  • Building Assemblies

    In order to reduce the risk of injury during assembly tasks, the workstation should be suited to the worker. A variable-height workstation, such as a tabletop affixed to a Scissor Lift Table, will allow any worker to adjust the surface to keep tasks within a safe range of motion.

    According to OSHA, hand tools used for assembly increase the risk of repetitive-motion injuries. They recommend using mechanical assists whenever possible. Remaining hand tools should have padded handles that extend across the worker's whole palm, and self-opening mechanisms where applicable.

  • Welding

    Welders in prefabrication shops sometimes bend or twist their bodies in order to complete certain welds. They might spend long minutes bent at the waist, leaning over a piece, or reaching up above their shoulders. In time, each of these movements begins to increase the risk of musculoskeletal injury.

    Again, the best response is to provide adjustable-height workstations. Scissor Lift Tables make ideal surfaces for small-scale welding, with their full-steel construction and a powder coating that will resist scratches and sparks.

When in doubt, provide some way for workers to reposition work themselves. Other helpful ergonomic interventions include anti-fatigue mats at workstations, the enforcement of regular breaks for stretching and moving, and padding the edges of work surfaces that employees might lean against.

Better Safety in Electrical Prefabrication Shops Contributes to Overall Success

Virtually every modern electrical contractor engages in some level of prefabrication or modularization during project planning. Some even rely on third-party prefabrication operations, specialized electricians who don't leave the shop at all. Given the rise of prefabrication in the electrical field, it has become a crucial point of competition within the industry.

In order to compete successfully, companies need to work toward greater efficiency and an unblemished safety record. Ergonomics lies at the heart of that effort. Tips like those listed above will help any electrical prefabrication shop cut down on injuries, reduce labor, speed up production, and ultimately run a tighter, more successful contracting business.


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"Ergonomics eTool: Solutions for Electrical Contractors." OSHA. Occupational Safety and Health Administration, United States Department of Labor, n.d. Web. 16 Aug. 2017.

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