- If servicing and/or maintenance is not being performed, while employees are awaiting the parts necessary to complete the repairs, can the LOTO locks be removed and replaced with either “Continuity” locks or “Out of Service” locks?
- Does this section of the compliance directive apply only to shift or personnel changes, or can it be applied to other scenarios (e.g., waiting for parts)?
- Does the application of a LOTO lock in the above scenario qualify as servicing and maintenance?
- Given the same scenario as above, if the equipment was still in place, but not in use, could a LOTO lock still be used?
- Can a LOTO lock be used to prevent the energization of a circuit to an abandoned or removed piece of equipment and, if yes, how is this different than “out of service”?
- Can a LOTO lock be used to prevent the energization of equipment that is waiting for parts and, if yes, why is this not considered “out of service”?
- Is there any guidance on how long a LOTO lock can be left on a piece of equipment while waiting for the part?
Background: A company has three (3) different types of locks that you define as follows:
- LOTO locks: locks applied by authorized employees to control the unexpected startup of equipment during servicing and maintenance. These locks meet the requirements of 29 CFR 1910.147(c)(5)(ii).
- Out of Service locks: locks used to prevent the unauthorized/ unintentional startup of the equipment that is not ready or able to operate (e.g., awaiting replacement parts, equipment that has been dismantled/deactivated, etc.).
- Continuity locks: locks used to hold the continuity of a lockout while servicing and maintenance is not being performed (Lock box setup, Shift Change, etc.) or to add an additional level of control by a department over a lockout.
Question 1: If servicing and/or maintenance is not being performed, while employees are awaiting the parts necessary to complete the repairs, can the LOTO locks be removed and replaced with either “Continuity” locks or “Out of Service” locks?
Response: The lockout/tagout standard, 29 CFR 1910.147, does not prohibit employer use of non-lockout devices (e.g., “Continuity” locks or “Out of Service” locks) while awaiting parts necessary to complete repairs, provided no employees are exposed to the potential hazards from unexpected energization or start-up of the machines or equipment, or release of stored energy during any servicing and/or maintenance activities. However, prior to employees resuming any servicing and/or maintenance work on machines or equipment that exposes them to the potential hazards from unexpected energization or start-up of the machines or equipment, the authorized employees must verify that the machines or equipment are isolated from any energy sources and apply a lockout or tagout device meeting the requirements of 29 CFR 1910.147.
Scenario: The Control of Hazardous Energy – Enforcement Policy and Inspection Procedures Directive (CPL 02-00-147), Chapter 3, Section XV, Shift or Personnel Changes, describes an example of methods that would provide the continuity of LOTO protection during shift or personnel change: “All authorized employees leave their personal LOTO devices in place until the job is completed. The energy cannot be restored, and the machine energized until all the employees have removed their personal LOTO devices.”
Question 2: Does this section of the compliance directive apply only to shift or personnel changes, or can it be applied to other scenarios (e.g., waiting for parts)?
Response: The referenced section of the CPL 02-00-147 describes methods of complying with requirements applicable to controlling energy during shift or personnel changes to provide a continuity of lockout or tagout protection throughout this transition period. See the responses to the questions below for further information on when lockout devices may be left in place.
Scenario: A machine is scheduled to be removed from the site. An electrician turns the disconnect switch to the “off” position and applies the company’s lockout device while he disconnects the power supply cables from the machine. The machine is removed from the site and no other equipment is connected to the disconnect switch. The electrician leaves the lockout device attached to the disconnect switch. This arrangement might be in place for an indefinite period of time, although no maintenance work is to be performed. (Please see scenario 4 in Mr. Jimmy Hill LOI related to the requirements of 1910.147 and Subpart S issued on November 30, 2010).
Question 3: Does the application of a LOTO lock in the above scenario qualify as servicing and maintenance?
Response: The work described in this scenario would be covered by Subpart S of OSHA’s standards, which addresses electrical safety requirements, and in particular 29 CFR 1910.333(b)(2). Subpart S is not limited to “servicing and maintenance,” and the work described in your scenario (i.e., removing power supply cables from the machine) involves electrical energy and exposure to electrical hazards, which would qualify as work requiring safety-related work practices under 29 CFR 1910.333(b)(2), Lockout and tagging. That provision requires that “While any employee is exposed to contact with parts of fixed electric equipment or circuits which have been deenergized, the circuits energizing the parts shall be locked out or tagged out or both…” which would cover both the electrician’s work deenergizing the machinery or equipment and the continued use of lockout or tagout devices on the deenergized disconnect switch. This is not in conflict with 1910.147(c)(5)(ii), because that provision requires that lockout and tagout devices shall be the only device(s) used for controlling energy and shall not be used for other purposes, and in this case, leaving the lockout device on the disconnect switch would still be “controlling energy” within the meaning of that provision.
Question 4: Given the same scenario as above, if the equipment was still in place, but not in use, could a LOTO lock still be used?
Response: Yes, a lockout device can be used for the purpose of controlling the electrical energy at the disconnect switch.
Question 5: Can a LOTO lock be used to prevent the energization of a circuit to an abandoned or removed piece of equipment, and if yes, how is this different than “out of service”?
Response: There are no prohibitions against the use of a lockout device to control hazardous energy, including when related to an abandoned circuit or out of service equipment.
Question 6: Can a LOTO lock be used to prevent the energization of equipment that is waiting for parts, and if yes, why is this not considered “out of service”?
Response: There are no prohibitions against the use of a lockout device to control hazardous energy for machines or equipment that are waiting for parts or out of service.
Question 7: Is there any guidance on how long a LOTO lock can be left on a piece of equipment while waiting for the part?
Response: OSHA does not specify any maximum timeframe a lockout device may be used to control hazardous energy while waiting on a part.
Source: https://www.osha.gov/laws-regs/standardinterpretations/2025-11-24