How often must e-stops be inspected?

OSHA does not address e-stop inspection or testing. However, in the absence of clear requirements, the agency can and does cite employers under The General Duty Clause and has cited employers for failure to ensure that emergency stop buttons functioned as intended. For example, in an March 22, 2007 General Duty Clause citation, the agency noted the following:

“Section 5(a)(1) of the Occupational Safety and Health Act of 1970: The employer did not furnish employment and a place of employment which were free from recognized hazards that were causing or likely to cause death or serious physical harm to employees in that employees were exposed to being struck-by and caught-in rotating parts ... the employer failed to provide an emergency stop at the operator control station...that would stop all motions of the machine that cause a hazardous condition, e.g., rotating parts, belts, gears, and cutting heads. Among other methods, one feasible and acceptable method to correct this hazard is to ensure that the “stop” and “emergency stop” functions on this machine... Conform to the requirements of the National Fire Protection Association (NFPA) standard 79; Electrical Standard for Industrial Machinery, 2007 edition; Section 9, “Control Circuits and Control Functions;” and Section 10, “Operator Interface and Control Devices.”” [emphasis added]