According to Article 100, an “Electrically Safe Work Condition” is a “state in which an electrical conductor or circuit part has been disconnected from energized parts, locked/tagged in accordance with established standards, tested to verify the absence of voltage, and, if necessary, temporarily grounded for personnel protection”.

NFPA 70E does NOT permit using a noncontact type tester (see image) when testing for the absence of voltage on electrical systems rated 1000 volts or less. Section 120.5(7) specifically requires the absence of voltage test to be conducted from “phase-to-phase” and “phase-to-ground”. This type of testing cannot be performed with a noncontact tester.

Section 120.5 provides guidelines on how to both establish and verify an electrically safe work condition. See below for more details on absence of voltage testing.

Below is a sample of NFPA 70E. For the complete section, see the actual NFPA 70E text at NFPA.ORG. Once there, click on the free access link to NFPA 70E.

120.5 Process for Establishing and Verifying an Electrically Safe Work Condition.

(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 all of the 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.

Exception No. 2 to 7: On electrical systems over 1000 volts, noncontact capacitive test instruments shall be permitted to be used to test each phase conductor.