Mike Dolt Enterprises
Mike Dolt Enterprises
User: billk554, Location: Moore, OK
Asked on: Wednesday, April 6, 2011 at 1:39 pm EDT
Answered on: Tuesday, May 14, 2024 at 3:51 am EDT
Question: we have a new director who wants machines locked out before working on them. great point. now the problem. if an operator uses the installed safety's (open a cover on a machine to clear a jam) the installed safety's function shuting down power to make entry to the area and clear out stuff. the safety director notices a light on on the machine and says the machine is not safe to work on becaused there is still electricity going to the machine. its the same when we push the stop button but the button is illuminated so he sees the light and says the machine still has power to it lock it out. now the operators are not doing any electrical work, they are just clearing a jam. the installed safety's are functioning, there is no danger of any other type of stored energy, where are the standards listed to define the duty of safety switches and their purpose?by the way . . .does anyone need a new safety director?
Standards for Safety Switches and Their Purpose ANSI/ASSE Z244.1-2016
Control of Hazardous Energy: Lockout/Tagout and Alternative Methods.
NFPA 70E
Standard for Electrical Safety in the Workplace.
Key Provisions Definition of Safety Switches (ANSI/ASSE Z244.1-2016): "A safety switch is a mechanically operated switch (e.g., interlock, limit switch, safety switch) designed to cut off all energy to a machine or other equipment." Purpose of Safety Switches (ANSI/ASSE Z244.1-2016): "Safety switches are used to prevent unexpected or unintended energization or startup of a machine or other equipment during service or maintenance activities." Stored Energy (NFPA 70E): "Stored energy sources include, but are not limited to, electric capacitors (including those inside electronic equipment), inductors (including those inside circuit boards and transformers), flywheels, accumulators, springs, and pressurized/hydraulic components."Application to the Situation
In the described situation, the safety switches are functioning properly by shutting off power to the machine when an operator opens a cover to clear a jam. This is not an electrical maintenance task, and there is no danger of stored energy. Therefore, the installed safety switches provide an adequate level of protection and lockout is not required.
Communication with the Safety Director Explain the purpose and function of the safety switches as defined in the standards. Provide evidence that the safety switches are working properly and there is no danger of stored energy. Emphasize that lockout is not necessary because the safety switches are providing the required level of protection.* Offer to provide training or resources to help the safety director understand the principles of lockout and the proper application of safety switches.If the safety director remains unconvinced, it may be necessary to involve higher-level management or consult with a qualified safety professional to resolve the issue. Flag for review