OSHA is seeking information on a possible update to the Control of Hazardous Energy [Lockout/Tagout (LOTO)] standard. Specifically, the agency is interested in comments on the use of control circuit-type devices to isolate energy, as well as evolving technology for robotics.

OSHA wants to learn how employers use control circuit-type devices, including information about the types of circuitry and safety procedures being used; limitations of their use to determine under what conditions control circuit-type devices could be used safely; new risks of worker exposure to hazardous energy as a result of increased interaction with robots; and whether the agency should change the LOTO standard to address these new risks.

The current LOTO standard was published in 1989. It requires that all sources of energy be controlled during servicing and maintenance of machines and equipment using an energy-isolating device. The standard specifies that control circuit-type devices cannot be used as energy-isolating devices, but technological advances may have improved the safety of these devices.

ANSI/ASSP Z244.1-2016, The Control of Hazardous Energy: Lockout, Tagout and Alternative Methods, includes information on these devices as a alternative method for preventing the release of hazardous energy. Annex S of Z244 discusses application of the standard in the semiconductor industry. "When isolation of the hazardous energy would prohibit the completion of certain tasks, using alternative methods is an allowed means of protecting the workers. In these special cases, the use of robust circuit control designs can provide a highly reliable engineered solution to control these hazardous energies." It also contains guidance on design strategies to address control circuit reliability.

Comments on OSHA's request are due by Aug. 18, 2019, via the federal e-Rulemaking portal.