According to NFPA 70E 120.2(A), “All electrical circuit conductors and …parts shall be considered energized until the source(s) of energy is (are) removed, at which time they shall be considered de-energized.”
Table130.7(C)(15)(A)(a) PPE is required to work on “energized” conductors.
For example: Open the box with 277v conductors, use a capacitive voltage tester (lights up), lock out/tag out the source, use capacitive voltage tester again (not lighting up), test capacitive voltage tester on a known live circuit (lights up) to verify tester is operational.
I have now proved the circuit is de-energized.
You are correct on two points, namely that “all electrical circuit parts and conductors shall be considered energized until the source(s) of energy is (are) removed, at which time they shall be considered de-energized”. And the third listed task in Table130.7(c)(15)(A)(a) does indeed state that in any equipment condition, “work on energized conductors and circuit parts, including voltage testing” requires arc flash PPE.
The need for PPE is removed if the circuit parts and conductors have been put into an “Electrically Safe Work Condition”, as Article 120 states. The second sentence in Article 120.2(A) states, “All electrical conductors and circuit parts shall not be considered to be in an electrically safe work condition until all of the applicable requirements of Article 120 have been met.”
I underlined the last sentence in your example. Unfortunately, you may not have proved the circuit is de-energized. Capacitive voltage testers usually do not function below 75 VAC. So even though the capacitive voltage tested did not light up, a voltage still may exist on the “target” circuit (the circuit a person is planning to touch or work on). The most accurate method to determine if a target circuit is de-energized is use a contact type tester, rated for the voltage being tested and capable of reading zero volts.
In the case of voltages greater than 600V, contact type testers may not be available or practical for use, so grounding is always required after testing with a proximity tester.
Please keep in mind that NFPA 70E®, Article 100, defines work as “intentionally coming in contact with energized electrical conductors or circuit parts with the hands, feet, or other body parts, with tools, probes, or with test equipment, regardless of the personal protective equipment (PPE) a person is wearing.” The definition continues by stating, “There are two categories of “working on”: Diagnostic (testing) is taking readings or measurements of electrical equipment with approved test equipment that does not require making any physical change to the equipment…”. Workers should have regular training on NPFA 70E and OSHA electrical safety standards.
So, when a person has to measure voltage on a target circuit to make certain it is at a zero voltage state, he or she is “working on” electrical conductors and circuit parts. Therefore, according to Table130.7(c)(15)(A)(a), he or she is required to wear arc flash PPE. And, according to Article 130.4(D), they are crossing the Restricted Approach Boundary and are required to wear shock PPE, namely insulated gloves with leather protectors.
When a true electrically safe work condition has been established, PPE is not required. But e-Hazard recommends that electrical workers wear daily wear (this is one of our 7 Electrical Safety Habits that prevent almost all fatalities from arc flash), which is arc rated to eliminate the risk of ignition. During testing, the need for PPE is critical. We recently investigated an accident in which the workers inside the Arc Flash Boundary were wearing street clothing and ONLY the worker doing the testing was in a flash suit. This is incorrect. Wear the PPE until all the conditions of the electrically safe work condition have been met.