While investigating the recovery of electrical burn victims, researchers discovered a distressing truth about their data: the use of safety equipment, such as PPE and insulated tools, was alarmingly low.
In fact, every electrical burn patient in the study had failed to follow all appropriate safety measures, but the problem isn’t limited to electrical work. ESFi reports that between 2011 and 2019, 68 percent of workplace electrical fatalities were attributed to non-electrical occupations. Electrical hazards exist throughout the workplace and impact workers who aren’t trained electricians or electrical contractors for a number of logical reasons.
A machine operator works on a machine that is powered by electricity and a mechanic does, too. They may be experts at their jobs, but they aren’t necessarily qualified people ready to establish and verify an electrically safe working condition. Facilities all over the world right now are reexamining how spaces are cleaned, where cleaning crews need to go and what they need to touch to keep spaces clean or disinfected. Every facility is different, with multiple work processes operating independently or in tandem—some of them requiring multiple steps and continual repetition of vital, but still repetitive, tasks.
It’s is very common for people to fail to verify aspects of important situations. Safety professionals, however, can’t simply cite human nature for cutting corners and call it a day. Safety training and protocols are designed to empower employees to take the time, every time, to protect themselves and others. Yet, electrical shocks and burns are still occurring in an alarming number of cases to workers who weren’t there to perform electrical work but were carrying out other tasks. That’s one reason so many safety experts want to prioritize the prevention of workplace injuries with design practices.
Processes and PPE can—and do—protect people, but addressing risk during the design of a system is a more effective way to reduce risk and mitigate hazards workers face.
Engineering for Safer Testing Outcomes
One place facilities are examining the risk of human error is in the mitigation of electrical incidents. When establishing an electrically safe work condition, the traditional method of verifying an absence of voltage relies on a manual process with a hand-held tester. To perform that test safely, a qualified person relies on additional layers of procedure, expert knowledge and proper use of equipment, including PPE. Each item on that list is a place where a human may, despite proper training and experience, make a mistake.
If any step in the process exposes a worker to electrical hazards, then it isn’t a question of whether that risk should be addressed, but how. The Hierarchy of Controls provides clear categories of risk mitigation strategies ranked in order of effectiveness. PPE and administrative controls, such as safety procedures, are at the bottom of the inverted pyramid. They are the least prioritized because although they control the risk—the hazard is still there. At the top of the hierarchy are design-related controls. These controls alter the process or equipment in a way that either eliminates the hazard, substitutes it for a lesser hazard or utilizes engineering controls to reduce exposure to the hazard.
For the verification of an electrically safe working condition, it is possible to replace the hand-held testing process with an engineered solution. An absence of voltage tester (AVT) is a permanently mounted tester designed to test for of absence of voltage, but unlike the traditional hand-held tester, the AVT completes the test without exposure to hazards.
Why Would an AVT Be Safer?
Hand-held voltage test instruments and AVTs both satisfy the requirements in NFPA 70E for testing for absence of voltage. Both methods test for phase-to-phase and phase-to-ground voltage at the point of work. Both the hand-held tester and the AVT confirm proper operation with a known voltage source. The main differences are in how the steps in the testing process are achieved:
*An AVT enables testing before doors, panels, or covers are removed, while a hand-held tester requires physical access to circuit parts during testing.
*Engineered with layers of requirements for fail-safes, an AVT automates a safety procedure and provides a consistent process which is less susceptible to human performance errors that are typical with hand-held testers.
*An AVT is permanently mounted and hardwired to the test point, the AVT produces reliable results, even in places that are difficult to test with hand-held testers. An AVT makes a more efficient process possible. While the hand-held testing process typically requires 10 to 20 minutes for a qualified person to complete properly, utilizing an AVT replaces it with a process that takes seconds and requires only the push of a button. In addition, the AVT can be integrated with other safety and controls, physically preventing access to an enclosure, control room or work area, until the absence of voltage has been confirmed. AVTs make it possible for both electrical and non-electrical workers to confirm absence of voltage without exposure to hazards.
What’s Wrong with Hand-Held Testing?
Voltage testing is critically important, and no one tool or procedure will ensure electrical safety in every situation. Hand-held testers, such as digital multimeters, will continue to be necessary, and facilities cannot discount the need for vigilance and improvement in all processes that require them. The AVT is designed to make one important, frequently performed process safer. The automated process subtracts all-too-common human factors from situations like:
*A process is interrupted, or a worker is distracted and accidentally skips a vital step.
*A worker repeatedly performs the process several times a day and becomes complacent.
*Time pressures or lack of negative consequences over time lead to improper or no PPE use.
There’s also one crucial difference between an AVT and manual testing that seems obvious but can often go overlooked: an AVT is built into the system to test exactly what it’s designed to test. When using hand-held testers, the equipment tested may or may not have been designed with the need for voltage testing in mind, with each piece of equipment (or particular installation of it) posing unique challenges that an experienced person must be aware of and remember in order to perform the test properly. Some areas of concern and technical issues that testers should be aware of include:
Using the right tester. There are many types and kinds of portable testers. Some may not be rated for the environment, meet the requirements for manually testing for absence of voltage, or may require a specific setting. In the case of the latter, making sure the setting is correct is absolutely vital. An AVT removes the setting error issue by being dedicated to the specific task. Lookalike equipment error. Many assets look identical and errors can happen in a facility or in the field when part of a process are performed on an adjacent or mislabeled piece of equipment. An AVT can help avoid these errors because it is installed on the equipment.
Barriers to safety. Barriers or guards are used in equipment to prevent accidental contact with energized parts. However, they can also prevent contact that is required for hand-held testers. When testing for absence of voltage be sure to consider if there are additional risks associated with removing a guard and whether good contact can be made through a barrier.
Skipping the self-test. Working environment difficulties can tempt workers to skip verifying the operation of a tester on a known voltage source (this also requires exposure to voltage). An AVT is designed with a built-in, known voltage source for self-testing.
Safety versus safety. Insulated busbars, finger-safe terminals or other safety options may make it difficult to assess where a proper contact can be made with a hand-held tester. If a worker mistakenly tests an insulated conductor, they may believe absence of voltage has been tested for, when it has not. Part of the AVT test sequence is confirmation that the AVT is in contact with a reliable test point.
Reliable ground required. Without a reliable ground reference point, a handheld tester can show zero volts even if voltage is present. An AVT must be installed with ground leads and will not indicate absence of voltage if the ground leads are not properly terminated.
Advancing Options for Safety
As technology continues to advance, so do our options for ensuring electrically safe working conditions in all types of facilities. As businesses design safety control measures into a system or work process, they are also realizing addition benefits like operating efficiencies in addition to the safety improvements those control measures provide. For more information on using AVTs for a more efficient, engineered approach to safety, reach out to your electrical infrastructure solution partner.