Verifying ZES is DIFFERENT for electrical workers!

Last week I posted the requirements for workers verifying a Zero Energy State (ZES), and it was ALL about operators and NOT electrical workers. In this post, I will explain the EXTRA steps that “qualified electrical workers” MUST DO BEFORE they begin their electrical work.

I will use the OSHA regulation for electrical work…1910.333 “Selection and use of Work Practices.” In this standard, it states the following:

1910.333(b)(2)(iv) Verification of deenergized condition. The requirements of this paragraph shall be met before any circuits or equipment can be considered and worked as deenergized.

1910.333(b)(2)(iv)(A) A qualified person shall operate the equipment operating controls or otherwise verify that the equipment cannot be restarted.

1910.333(b)(2)(iv)(B) A qualified person shall use test equipment to test the circuit elements and electrical parts of equipment to which employees will be exposed and shall verify that the circuit elements and equipment parts are deenergized. The test shall also determine if any energized condition exists as a result of inadvertently induced voltage or unrelated voltage backfeed even though specific parts of the circuit have been deenergized and presumed to be safe. If the circuit to be tested is over 600 volts, nominal, the test equipment shall be checked for proper operation immediately after this test.

Notice that (A) above is much like what an operator will do as part of their LOTO. Still, electrical workers and I should stress QUALIFIED ELECTRICAL WORKERS are REQUIRED to use test equipment to test circuit elements and electrical parts to VERIFY ZES. See part B above.

Many facilities still do not have Electrical Safety Related Work Practices to cover the activities of their electrical workers, and VERY FEW LOTO programs will distinguish the procedures for ZES verification for electrical workers vs. the operator who runs the equipment. Most LOTO programs use language that instructs the authorized employee to try and start the machine/equipment using the normal start buttons and does not mention electrical workers using test equipment to test circuit elements and electrical parts to VERIFY ZES.

OSHA will not use 1910.147 to cite for this program/procedural deficiencies, but instead, use 1910.333(b)(2)(iv)(B). Bottom line…Qualified Electrical Workers MUST use test equipment to VERIFY ZES BEFORE they begin work.

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