Page 62 - OHS, October 2020

ELECTRICAL SAFETY
2021 Updates to NFPA 70E
What you need to know about absence of voltage testing.
BY RACHEL BUGARIS The National Fire Protection Association (NFPA) is a trade association that develops and maintains various standards and codes designed to prevent injury and economic loss caused by fire and electrical related hazards. The organization publishes NFPA 70E, the Standard for
Electrical Safety in the Workplace.
Many companies use NFPA 70E when they are
developing their electrical safety program. Because NFPA 70E is regularly updated every three years, it incorporates new technology and practices that may not yet be noted in regulations or other standards.
One area where technology has been incorporated to stimulate innovative solutions is absence of voltage testing.
The Absence of Voltage Tester (AVT), is a permanently mounted solution that makes testing for an absence of voltage safer and more efficient.
120.5 Process for Establishing and Verifying an Electrically Safe Work Condition
The process for establishing and verifying an electrically safe work condition is described in Article 120.5. This is a multi-step process that includes identifying sources, de-energizing the supply, applying lockout/tagout devices in accordance with established procedures and verifying the absence of voltage.
Electrical equipment should be treated as energized until proven otherwise. Step (7) and Exception No. 1 to (7) address verifying the absence of voltage. There are two methods that can be used: portable test instruments, such as a digital multimeter or voltage detector, or permanently mounted absence of voltage testers (AVT). From NFPA 70E:
NFPA 70E-2021 120.5
(7) Use an adequately rated portable test instrument to test each phase conductor or circuit part to test for the absence of voltage. Test each phase conductor or circuit part both phase-to-phase and phase-to-ground. Before and after each test, determine that the test instrument is operating satisfactorily through verification on any known voltage source. Exception No. 1 to (7): An adequately rated permanently mounted absence of voltage tester shall be permitted to be used to test for the absence of voltage of the conductors or circuit parts at the work location, provided it meets the all following requirements:
(1) It is permanently mounted and installed in accordance with the manufacturer’s instructions and tests the conductors and circuit parts at the point of work;
(2) It is listed and labeled for the purpose of testing for the absence of voltage;
(3) It tests each phase conductor or circuit part both phase-to-phase and phase-to-ground; (4) The test device is verified as operating satisfactorily on any known voltage source before and after testing for the absence of voltage.
Informational Note No. 2: For additional information on rating and design requirements for permanently mounted absence of voltage testers, refer to UL 1436, Outlet Circuit Testers and Other Similar Indicating Devices.
In NFPA standards, an exception is an alternate method to comply with a mandatory requirement. Thismeansthatworkerscanchoosetouseeithera portable test instrument or a permanently mounted absence of voltage tester to verify the absence of voltage,butbothmethodsarenotrequired.
Although Exception No. 1 has been in NFPA 70E since the 2018 edition, recent updates in 2021 add clarity by changing “test device” to “absence of voltage tester.”
As the new Informational Note No. 2 states, more information on permanently mounted AVTs can be found in the product standard for absence of voltage testers, UL 1436.
This new reference to UL 1436 is important because of item (2) in Exception 1 – the requirement to be listed and labeled for the purpose of testing for the absence of voltage.
There are several types of permanently mounted products, some of which are listed and labeled for other purposes, but do not comply with absence of voltage testing listing and labeling requirements. Permanently mounted products are not all equal so be sure to look for the UL 1436 listing.
To further improve readability, terminology was updated to remain consistent with the rest of the standard. In several instances, “verify” was changed to “test for” (verify is used to determine if a test instrument is operating properly, while testing is used to describe the process of checking for a circuit condition). Similarly, “deenergized” was replaced with “absence of voltage” throughout this section.
58 Occupational Health & Safety | OCTOBER 2020
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