Low Voltage But Not Low Risk

By Russ Munyan | May 15, 2009




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The good news is that the electrical current through low-voltage cabling—such as telecommunications, security or video—is not strong enough to cause a fatal electric shock. The bad news is there still are very real safety risks when performing low-voltage installations.

“Even on low-voltage installations, it’s easy for contractors to have a sense of complacency that can build a false sense of security,” said Michael Johnston, executive director of standards and safety for the National Electrical Contractors Association (NECA). “That’s why it is important that contractors follow the National Electrical Code (NEC) when they are performing any installation, including low voltage.”

He pointed out that Chapter 7, Special Conditions, and Chapter 8, Communications Systems, include topics especially relevant to low-voltage installations. Johnston cautioned that low-voltage contractors should be concerned about secondary shock hazards.

“Even low-voltage installers can still experience unsettling shocks, especially if they are working in an unsafe environment, such as if they are ungrounded or standing on a wet spot,” Johnston said. “While it’s unlikely that such shocks will cause serious injury by themselves, they certainly could literally knock someone off balance, which could be a real safety risk if an installer were standing on a ladder.

“In addition, an arc in a low-voltage system has the same potential for igniting explosive materials as one in a 120-plus-volt system. Chapter 5 of the NEC provides rules for installing electrical wiring of any voltage in a hazardous (classified) location, specifically those locations with high concentrations of flammable or combustible liquids, flammable or combustible vapors, conductive and combustible dusts, and so forth.”

Don’t go in blind

Phil Janeway, Codes Committee chair for BICSI, said low-voltage installers need to know how to recognize and stay away from higher voltage electrical cables. BICSI is a professional association supporting the information transport systems (ITS) industry.

“Most low-voltage cables at some point cross connect with devices that do carry a dangerous electrical current, such as electronic switches, multiplexing equipment and PBX [private branch exchange] systems,” Janeway said. “So it’s not like there’s never a high-voltage risk when installing low voltage. Because of the environments that you’re in, there’s almost always a high-voltage risk of some sort when working around electronics.

“A contractor needs to make sure that his installers know when to stop and get a licensed and experienced electrician on the job,” he said. “It’s important that they recognize what they are working with. Don’t let them go in blind. Have them use a VOM [volt-ohm milliammeter] meter to determine if they are working in a high- or low-voltage environment. But if installers are asked to install a high-voltage circuit to the electronics and they are not qualified, then their safety is compromised.”

Fiber optics

Fiber optic cabling is a low-voltage technology that has some unique installation safety requirements, said John Jay, manager of Corning Inc.’s Optical Fiber’s applications engineering group, Corning, N.Y.

For starters, installers performing field terminations of fiber optic cables need to diligently track and manage unused glass shards that have been cleaved from a cable for field terminations.

“Those are like splinters, only they are a lot harder to see or remove, especially when they get into a fabric or a weave,” Jay said.

One of the best ways to secure severed pieces of glass is with a simple loop of tape, he said, adding, “that way, there are no fingers trying to pick up or manage them.”

There also are commercially available fiber optic disposal units from various manufacturers that are inexpensive and effective.

Eye safety is an important concern when working with fiber optic cables. Fiber shards in an eye can be both highly painful and damaging, so it is important that installers wear safety glasses when working with fiber and that they not touch their faces until washing their hands. And it is never a good idea to look directly into a fiber optic cable that could possibly have a laser current surging through it, Jay said.

He also cautions that fiber optic connectors should be kept clean because dirt on a connector end can rapidly oxidize when receiving a signal, which creates both a fire and functionality risk. And an installer should take extra care when using a fusion splicer, which fuses fibers together using an electric arc. Splicing workspaces should be dry and clean and free from any flammable fumes, including those from isopropyl alcohol, which often is used to clean fiber optics.

A lot to say about safety

Reese Electric, a multishop contractor based in North Bend, Ore., understands the importance of low-voltage and jobsite safety. Reese was the 2008 first-place winner of the Associated General Contractors/Willis Construction Safety Excellence Award for specialty contractors that operated less than 100,000 work hours. Not surprisingly, Reese Electric owner Randy Rema has a lot to say about safety.

“Low-voltage work has many of the same hazards as any other construction trade,” he said. “The most important thing I can do is to empower my employees to make safety-related decisions while on the job. My crews all have the power to stop work if they are exposed to an unsafe condition. And our guys also have to know that management will back them up in those situations, or the whole idea of employee empowerment goes out the window.”

Rema shared many anecdotes about occasions in which his crews have done just that, stopping work in unsafe situations until the risks had been addressed. There was the time that a crew discovered a plethora of exposed hypodermic needles of unknown origin littering the crawl space of a building where Reese Electric crews had been directed to perform work. Another time, a crew observed what appeared to be asbestos poking out of pipe insulation in the attic of an old school building.

His men were not chastised for stopping work in those circumstances; in fact, they were affirmed for making the right decisions to pull off.

“It might not even be a risk facing them,” Rema said. “If my guys see something unsafe for another company or trade, I want them to stop work until the situation is dealt with. If someone is doing something unsafe—I don’t care who it is—tell him to stop. If necessary, report it to the general contractor. But don’t just keep working if there is something unsafe going on.”

Rema explained part of his motivation: “I was once on a job site where there was a serious injury. Production from everyone on that entire project—not just the company that had the accident—was way down for two weeks. It took the whole project to practically a standstill.”

Rema also stressed the importance of identifying hazards and eliminating them. That includes looking for and dealing with trip hazards, choosing to safely move equipment and using fall protection. It also means identifying what to do when hazards cannot be eliminated.

“Being able to tell the difference means training and education,” he said. “Your people need to know what to do and who to call when they get into a situation that is beyond them.”

That is why Reese Electric conducts mandatory monthly safety meetings for its staff. About eight months out of each year, Rema uses external resources, such as local safety committee representatives, Associated General Contractors loss consultants, or a local Occupational Safety and Health Administration (OSHA) safety compliance officer. Once a year, the meetings focus on safely using the company’s heavy equipment. And for the remaining months, they focus on current hot topics to which the crews need to be exposed.

Rema does not only use his local OSHA compliance officer for monthly safety meetings.

“We find that as we spend time with him, he gets used to us and sees our commitment to safety, and our installers get used to him. We sometimes walk potentially risky job sites [with] the OSHA officer before work ever gets started. All of that helps everyone be more comfortable with one another so that we can work together to ensure safe workplaces.”

Finally, Rema believes that employee recognition is an important part of a company’s safety strategy. For Reese Electric, that means an annual company-wide safety awards banquet with recognition for everyone in the company.

“But we would not have those if we started having a string of accidents,” Rema said.

While recognition costs the company money, Rema said his company’s lower insurance costs help pay for them.

“And it’s not all about money,” he said. “The personal and financial cost would be terrible if our safety record were not under control. Everyone on our staff is really proud of our safety record and of the awards that we have won. And you can be sure that no one wants to be the first person to mess that up and get hurt.”

MUNYAN is a freelance writer in Olathe, Kan., specializing in technical and business writing. He can be reached at

About The Author

Russ Munyan is a freelance writer in Olathe, Kan., specializing in technical and business writing. He can be reached at





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