Working on or near energized circuits is not something most electricians want to do, but often it is necessary. And in those situations, it is imperative to use the proper safety gear, protective clothing and insulated hand tools.

True insulated tools are identified with the international 1,000-volt rating symbol, certifying they have been individually subjected to 10,000 volts and passed other tests stipulated in the ASTM standard F1505. Genuine insulated tools also comply with the International Electromechanical Commission (IEC) 60900 standard.

The National Fire Protection Association (NFPA) 70e standard addresses safety when working around exposed, energized circuits, and complying with its provisions will result in compliance with OSHA regulations. NFPA and other standards provide effective guidelines for safety, but they are not enforceable. OSHA enforces its standards, including those pertaining to shock and arc hazards, requiring the use of insulated tools.

Manufacturers and trainers caution that, with today’s emphasis on tool ergonomics, many hand tools have cushioned grips that are not insulated. Always look for the 1,000-volt symbol to confirm a tool qualifies for the insulated category.

Insulated versions of most basic hand tools used by electricians are available from specialist suppliers, such as Cementex Products and Certified Insulated Tools (CIP), and other tool companies, including Klein Tools, Ideal Industries and Channellock.

As it has been with most basic hand tools, ergonomics is a design consideration with insulated tools. Weight, comfort of grips and thumb guards are among ergonomic improvements on some of today’s insulated tool models.

The most commonly used insulated hand tools necessary for electrical work would be the different styles of insulated screwdrivers—Phillips, mechanics, flat and cabinet tips—as well as varying styles of insulated pliers, including linesman’s, needle nose and diagonals, said Jeff Russo, Cementex vice president and chief operating officer.

“Recognition of the need to use insulated hand tools has grown significantly in the last few years,” Russo said. “And along with that, so has the need for more various types of insulated hand tools, not just pliers and screwdrivers. The use of hex wrenches, open-end and box-end wrenches along with sockets, ratchets and torque wrenches can be equally as important. Providing workers with the proper insulated hand tools to do their job safely is as important as providing insulating rubber gloves and flame-retardant clothing.”

Russo added that insulated hand tools have been considered by some as expensive tools with limited value. However, that is changing. Recognizing that the insulated tools protect them from inadvertent contact with any known or unknown source of energy helps make electricians safer and more productive.

“Most manufacturers in the UnitedStates are using a high-grade carbon steel that is heat treated for overall durability and has either a black oxide or chrome-plated finish,” Russo said. “This process consists of a coat of liquid-based material on a tool through a controlled coating process. This form of coating can be done in either a single- or double-dipped fashion. Other methods include injection-molded parts and grips or injection molding over tools.”

Insulated hand tools have a financial impact on a company, Russo said.

“While there is an expense for these tools,” he said, “there are more benefits. The use of insulated tools makes working on or near energized sources safer and more manageable for companies, as it can produce safer electrical workers, better maintained equipment, and financially speaking, those two generally create a working environment that is hazard free, which contributes to a better bottom line.”

Ben Bird, CIP vice president, believes one of the most significant advances in insulated tools is the development of tools made of composite materials.

“Composite tools,” Bird said, “are durable, lighter in weight and slimmer than other types of insulated tools, allowing access to extremely tight areas. Composites allow the total elimination of insulating coatings that become nicked, cut or torn during normal use. If kept clean and dry, there is no conductive path back to the user’s hand.”

The latest development in this area, Bird said, is the introduction of screwdrivers and nut drivers manufactured from braided, military-grade fiberglass composite over a tough, polymer core.

“Composite tools,” he said, “take advantage of the inherent nonconductive, lightweight, and high-strength properties of composite materials and eliminate the need for insulation coatings, which can be cut, nicked or torn during normal use. Composite nut drivers can be used in small areas where many times coated tools are too thick to fit.”

The strength of composite plastics should not be a concern, Bird said.

“A strong person can apply torque at 6 foot-pounds,” Bird said. “Metal yields at 10 foot-pounds, and composite fails at 20 foot-pounds.

Russ Goldmann II, Klein Tools, director of product design and development, said that ASTM and IEC publish standards for insulated tools, which are publicly available for purchase.

“While the criteria and subsequent testing of these criteria vary by tool, there are some commonalities,” Goldmann said. “In order to be rated as 1,000-volt insulated products, these tools must pass a 10,000-volt dielectric test (10 times their rated value), meet ambient and cold temperature impact tests, and pass flame tests for starters. There also are dimensional criteria and pull-off tests to make sure the insulation doesn’t become separated from the tool.”

Goldmann noted recognition of electrical hazards and protective measures have evolved since OSHA first addressed electrocution hazards.

“Today,” Goldmann said, “the NFPA recognizes three electrical hazards: shock, arc flash and arc blast. And arc flash presently is receiving a lot of attention. Insulated tools, along with protective equipment and clothing, can help protect workers against these hazards.”

Bruce Hartranft, Ideal Industries unit manager, said new methods of insulating tools have been developed since the first dipped models were made that drastically improve the function and feel of the tool.

“The two most important are injection-molded products and composite tools,” he said. “Injection-molded tools allow handles to be shaped to best fit the electrician’s hand, rather than having to match the shape of the tool like dipped tools do. In addition to the ergonomics this provides, it also allows manufacturers to use insulating materials that are more comfortable in the hand, such as softer plastic, and that are more durable, like harder plastic. At first this might seem to be contradictory, but consider a molded pliers handle: The underlying layer can be molded of extra-tough, hard plastic that resists damage, cuts, wear, etc., while the overlying layer—which is usually a different color for the visual safety check—can be molded of a soft, comfortable, ergonomic material that feels more comfortable in the hand.”

Composite tools are almost entirely made of a composite plastic material, usually glass-filled plastic, Hartranft said.

“These tools,” he said, “are generally more expensive than standard tools and are not always as strong, but they can be a good alternative because they are not susceptible to failure from damage to the tool. If a composite-shaft screwdriver gets cut or nicked, it is still safe to use because the shaft is plastic all the way through.”

Hartranft recalled that before insulted tools were available, electricians wrapped electrical tape around pliers’ handles and screwdriver shafts.

“This was obviously an unreliable and risky way to protect from shock,” he said. “Dipped grips were introduced and have been around for a long time, and eventually manufacturers thickened the plastisol grip to provide more protection then began using two-color dipping developed to help warn a user when the grips had been damaged.”

Hartranft said today’s insulated tools are better than earlier products because there are standards that dictate their design and testing.

“Knowing that today’s tools have been designed and tested to pass these standards,” he said, “provides users an extra level of confidence that they will perform appropriately when used in conjunction with the safe work practices found in OSHA and NFPA requirements.”

Proper use and care prolongs the life and insulating properties of insulated tools. They should be carried and stored in a manner that will minimize damage to insulation and stored away from sources of heat. Contaminants should be removed from tools immediately and thoroughly dried before storage. Harsh detergents can prematurely age plastic coatings.

“The only way a tool will lose its insulating properties is if the insulation is compromised, exposing the underlying conductive material,” Hartranft said. “This is why it’s good to have two-color handles providing a visual safety check to know if the insulation has been damaged. If the plastic is cut, cracked, scuffed, etc., then the insulating property of that plastic has been lost. For composite tools, cracks or damage may cause the tool to break, which can lead to other safety concerns.”

GRIFFIN, a construction and tools writer from Oklahoma City, can be reached at 405.748.5256 or