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Environmental Health and Safety

Control of Hazardous Energy Sources (Lockout/Tagout Program)

VII. ENERGY CONTROL

A. GENERAL RULE

All equipment shall be locked out prior to cleaning, servicing, or adjustment operations to protect against accidental or inadvertent operation when such operation could cause injury to personnel. Employees shall not attempt to operate any switch, valve, or other energy isolating device bearing a lock. The general rule which shall be followed is this: “If an energy isolating device can be locked out, it must be locked out.”

B. IDENTIFICATION OF SOURCES

All departmental equipment with hazardous energy sources subject to lockout/tagout requirements shall be identified by department personnel. This includes locating, identifying, and labeling all isolating devices which apply to departmental equipment subject to lock out tag out requirements.
An initial survey is required to identify all hazardous energy sources, including a physical inspection possibly in combination with review of drawings and equipment manuals.
Documentation pertaining to disconnecting means shall include the equipment supplied, energy type, and magnitude.
The survey must be performed by responsible persons who are thoroughly familiar with equipment operation and associated hazards, in order to identify which machinery should be locked and blocked out.

C. EXCLUDED ACTIVITIES AND EQUIPMENT

The following activities are excluded from lockout requirements:

Minor tool changes and adjustments and other minor servicing activities, which take place during normal production operations if they are routine, repetitive, and integral to the use of the equipment or machinery for production, provided that the work is performed using alternative measures which provide effective protection. Effective alternative worker protection measures must be documented and approved by management.
When equipment design and performance limitations dictate that effective alternative worker protection be provided and lockout is not feasible. Effective alternative worker protection measures must be documented and approved by management.
When machinery or equipment must be capable of movement in order to perform a maintenance task, such as a cleaning operation, employees can use extension tools such as extended swabs, brushes, and scrapers to protect themselves from injury. Employees shall receive thorough training in the safe use and maintenance of these items.
Work on cord and plug connected electric equipment or systems when it is unplugged, de-energized, physically removed from the wiring system, where suitable tagging procedures are used, where the disconnecting means is accessible only to personnel instructed in tagging procedures, and the operation is effectively blocked or all stored energy devices which present a hazard are dissipated such as capacitors, pneumatic, or spring loaded mechanisms.

D. MAINTENANCE OF REPETITIVE PROCESS MACHINES

On repetitive process machines which require power or current continuance and where repair, adjustment, and testing cannot be accomplished with the energy source disconnected, such operations may be performed under the following conditions:

The operating station where the machine may be activated must at all times be under the control of a qualified operator. Where machine configuration or size requires that the operator leave the control station to install tools and where machine elements may move rapidly if activated, these elements must be separately locked out.
All participants must be in clear view of the operator or in constant communication with each other.
All participants must be beyond the reach of the machine elements which may be hazardous.
During repair procedures where mechanical components are being adjusted or replaced, the machine shall be de-energized or disconnected from its power source.

E. REQUIREMENTS FOR LOCKOUT DEVICES

Departments with departmental equipment subject to lock out tag out requirements shall be responsible for providing a sufficient number of lockout devices. Lockout devices shall:

Be designated for exclusive use as energy source lockout devices, and cannot be used for other purposes such as securing toolboxes or lockers.
Be standardized on the basis of color, shape, and/or size.
Indicate the identity of the person applying the device.
Be substantial enough to minimize early or accidental removal.
Be accessible only by the designated employee to which it was issued through use of a specific key.
Be removed only by the employee who placed them. See exception in Release From Lockout/Tagout section.
Be removed upon completion of the work and after the installation of the protective guards and/or safety interlock systems.

F. REQUIREMENTS FOR TAGOUT DEVICES

Tags shall be used as a means to prevent accidental injury or illness to employees who are exposed to hazardous or potentially hazardous conditions, equipment, or operations which are out of the ordinary, unexpected, or not readily apparent. Tags shall be used until the identified hazard is eliminated or the hazardous operation is completed. Tags need not be used where signs, guarding, or other positive means of protection are being used.

Tagout devices must include:

a. A statement prohibiting unauthorized removal.

b. A warning of the specific hazardous condition represented by the equipment to which they are attached, which shall be stated through the use of clearly understood legends such as “Do Not Operate,” “Do Not Close,” or “Do Not Start.”

c. A signal word such as “Danger” or “Caution”. This shall be readable at a minimum distance of five feet and shall be understandable to all employees who may be exposed to the identified hazard.

d. The reason for placing the tag,

e. A major message indicating the specific hazardous condition or the instruction to be communicated to the employee. This shall be presented in either pictographs, written text, or both and shall be understandable to all employees who may be exposed to the identified hazard. All affected employees shall be informed as to the meaning of the various tags used throughout the workplace and what special precautions are necessary.

f. The identity of the employee applying the tag.

g. Information to contact the employee placing the tag.

h. The date and time the tag was placed.
Tagout devices shall be:

a. Used in addition to locks.

b. Removed only by the employee who placed them. See exception in Release From Lockout/Tagout section.

c. Removed upon completion of the work and after the installation of the protective guards and/or safety interlock systems.

d. Standardized on the basis of color, shape, size, print style and/or format.

e. Affixed as close as safely possible to the hazards by a positive means such as string, wire, or adhesive that prevents their loss or unintentional removal.
The means of attachment for tagout devices must meet the following criteria:

a. Be able to be affixed by hand.

b. Be non-reusable.

c. Be self-locking with a minimum unlocking strength of 50 lbs.

d. Be capable of withstanding the environmental conditions to which they are exposed.

(Note: A simple device which meets these criteria is a one-piece nylon cable tie.)
Workers must receive instruction on the following limitations and requirements of tags:

a. They do not provide a physical restraint.

b. They are little more than warning devices and may evoke a false sense of security unless their meaning is clearly understood.

c. They must be legible and understandable by all employees.

d. Both tags and attachment devices must meet certain requirements as specified in this section, and must be securely attached so that they cannot be inadvertently detached.

e. Tags are not to be removed, bypassed, obscured, ignored or otherwise invalidated without proper authorization.

G. USE OF BLOCKS

Suitable blocks shall be used as safety devices for making a piece of equipment safe to be repaired or serviced. Blocks must be placed under any equipment that might move by sliding, falling, or rolling.
Another form of blocking is the placement of a blind. A blind is a disk of metal placed in a pipe to ensure that no air, steam, or other substance will pass through that point if the system is activated.
Before installing blinds or blocks the pressure must be released from steam, air, and hydraulic lines. Coiled springs, spring-loaded devices, or suspended loads must also be released so that their stored energy will not result in movement.

H. PLANNING FOR LOCKOUT

An initial survey shall be carried out to determine which switches, valves, or other energy isolating devices apply to the equipment being locked out. More than one energy source may be involved and shall be considered in the survey. See “Energy Control, Identification of Sources” section. Any questionable identification of sources shall be cleared by the employees with their supervisors.
Before lockout is implemented, the supervisor must give job authorization. Only supervisors or authorized employees shall designate duties and responsibilities relating to the actual details of the lockout/tagout.
Energy isolating devices shall be operated only by authorized employees or under the direct supervision of authorized employees. Where high voltages greater than 480V are involved, the electrician supervisor shall be responsible for turning off the main power controls.
For complex systems, a written checklist shall be prepared for equipment access, lockout/tagout, clearance, release, and start-up.

I. LOCKOUT/TAGOUT STANDARD OPERATING PROCEDURE

Before any employee performs maintenance, repairing, cleaning, servicing, or adjusting on a machine where unexpected start up of stored energy could occur and cause injury, the machine shall be isolated. All energy sources which could activate the machine must be locked out.

The authorized employee who turns off a machine shall have knowledge of the type, magnitude and hazards of the energy and the method to control the energy.
The authorized employee shall notify all affected employees that a lockout is required and the reason. If applicable, there shall be coordination between affected departments.
If the equipment is operating, it shall be shut down by the normal stopping procedure. The employee shall check to be sure that no one is operating the machinery before turning off the power. The machine operator shall be informed before the power is turned off. Personnel who are knowledgeable about the equipment operation including shut down and restart procedures shall be involved.
The energy isolating device shall be operated so the energy source is disconnected from the equipment. Stored energy shall also be dissipated or restrained. For example, any mechanism under load or pressure, such as springs, shall be released and blocked and steam, air, and hydraulic lines shall be bled, drained, and cleaned out.
The energy isolating device shall be locked and tagged out with an assigned individual lock. Tags shall be attached to the energy isolating device and to the normal operating control to prevent operation. All energy sources which could activate the machine shall be locked out. If more than one employee is required to lockout equipment, each employee shall place a lock and tag on the energy isolating device or a group lock out device can be used. A single lock may be used to lockout the machine or equipment with the key being placed in a lockout box or cabinet which allows the use of multiple locks to secure it. Each employee shall then use their own lock to secure the box or cabinet. As each person no longer needs to maintain their lockout protection, that person shall remove their lock from the box or cabinet. If a supervisor locks out equipment for an entire crew, they are responsible for carrying out all of the lock out procedures and informing the crew when it is safe to work on the equipment.
The authorized employee shall ensure that no personnel can be exposed and check that the energy sources are disconnected by operating the normal controls to ensure that the equipment will not operate. If there is a possibility of re-accumulation of stored energy, then verification of isolation shall be continued until maintenance is complete.
A qualified person shall use calibrated 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 de-energized and isolated. The main valve or main electrical disconnect must be tested to be sure that the power to the machine is off. All energy sources which could activate the machine must be locked out.
The operating controls shall be returned to the neutral or off position.
The equipment is locked out.
Accident prevention tags shall be attached.
No one shall remove the lock without proper authority.
If there is a need to temporarily remove lockout/tagout devices for testing of the equipment as part of the repair or maintenance procedure after it is locked out, the following steps shall apply:

a. Clear the equipment of tools and materials.

b. Ensure that machine components are operationally intact, including guards.

c. Clear personnel.

d. Notify affected employees that lockout/tagout devices have been removed.

e. Clear the locks and tags according to the established procedure in the Release From Lockout/Tagout section.

f. Proceed with the test.

g. Disconnect the energy source and lock and tag the controls to continue work.
Care shall be taken to ensure that lockout/tagout information is transmitted between work shift crews.

J. RELEASE FROM LOCKOUT/TAGOUT

When the job is complete and equipment is ready for testing or normal service, an authorized person shall check the equipment area to see that no one is exposed.
Nonessential items shall be removed and machine or equipment components including guards and safety devices shall be operationally intact. Defective guards shall be repaired or replaced before removing locks and tags.
When equipment is clear, authorized employees shall remove all locks and tags using the correct removal sequence.
As a general rule, no one shall remove a lock or tag except the person who applied the device.

Exception: When the authorized employee who applied the lockout or tagout device (installer) is not available to remove it, that device may be removed under the direction of the installer’s immediate supervisor. If the lock is removed by someone other than the installer, safety equivalent to the original process of having only the installer remove the device shall be maintained. The specific procedure for removal of the lock shall include at least the following elements:

a. Verification by the immediate supervisor that the employee who applied the device is not at the facility,

b. Making all reasonable efforts to contact the authorized employee to inform them that his/her lockout or tagout device has been removed, and

c. Ensuring that the authorized employee has this knowledge before they resume work at the facility.
Affected employees shall be informed that the lockout/tagout devices have been removed.
A visual check shall be made before restoring energy to ensure that everyone is physically clear of the equipment.
The energy isolating device shall be operated to restore energy to the equipment after ensuring that no one is exposed.

K. EMERGENCY LOCK REMOVAL

The campus Lock Shop is the only authorized purchasing agent for locking devices. They will procure and provide any employee with a lock for use in a lock-out / tag-out situation. If it is determined that an emergency exists, and that a lock must be removed (pending determination of a safe environment), the campus lock shop can provide the necessary key for any lock.
Should a dire emergency exist, and it has been determined that the environment is safe, a lock may be removed in any manner that will not constitute an un-safe situation.

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This page last updated May 21, 2008
Site contact: UCO Web Support


	Business and Financial Affairs > Environmental Health and Safety > Industrial Safety > Hazardous Energy >
	Environmental Health and Safety Control of Hazardous Energy Sources (Lockout/Tagout Program) VII. ENERGY CONTROL A. GENERAL RULE All equipment shall be locked out prior to cleaning, servicing, or adjustment operations to protect against accidental or inadvertent operation when such operation could cause injury to personnel. Employees shall not attempt to operate any switch, valve, or other energy isolating device bearing a lock. The general rule which shall be followed is this: “If an energy isolating device can be locked out, it must be locked out.” B. IDENTIFICATION OF SOURCES All departmental equipment with hazardous energy sources subject to lockout/tagout requirements shall be identified by department personnel. This includes locating, identifying, and labeling all isolating devices which apply to departmental equipment subject to lock out tag out requirements. An initial survey is required to identify all hazardous energy sources, including a physical inspection possibly in combination with review of drawings and equipment manuals. Documentation pertaining to disconnecting means shall include the equipment supplied, energy type, and magnitude. The survey must be performed by responsible persons who are thoroughly familiar with equipment operation and associated hazards, in order to identify which machinery should be locked and blocked out. C. EXCLUDED ACTIVITIES AND EQUIPMENT The following activities are excluded from lockout requirements: Minor tool changes and adjustments and other minor servicing activities, which take place during normal production operations if they are routine, repetitive, and integral to the use of the equipment or machinery for production, provided that the work is performed using alternative measures which provide effective protection. Effective alternative worker protection measures must be documented and approved by management. When equipment design and performance limitations dictate that effective alternative worker protection be provided and lockout is not feasible. Effective alternative worker protection measures must be documented and approved by management. When machinery or equipment must be capable of movement in order to perform a maintenance task, such as a cleaning operation, employees can use extension tools such as extended swabs, brushes, and scrapers to protect themselves from injury. Employees shall receive thorough training in the safe use and maintenance of these items. Work on cord and plug connected electric equipment or systems when it is unplugged, de-energized, physically removed from the wiring system, where suitable tagging procedures are used, where the disconnecting means is accessible only to personnel instructed in tagging procedures, and the operation is effectively blocked or all stored energy devices which present a hazard are dissipated such as capacitors, pneumatic, or spring loaded mechanisms. D. MAINTENANCE OF REPETITIVE PROCESS MACHINES On repetitive process machines which require power or current continuance and where repair, adjustment, and testing cannot be accomplished with the energy source disconnected, such operations may be performed under the following conditions: The operating station where the machine may be activated must at all times be under the control of a qualified operator. Where machine configuration or size requires that the operator leave the control station to install tools and where machine elements may move rapidly if activated, these elements must be separately locked out. All participants must be in clear view of the operator or in constant communication with each other. All participants must be beyond the reach of the machine elements which may be hazardous. During repair procedures where mechanical components are being adjusted or replaced, the machine shall be de-energized or disconnected from its power source. E. REQUIREMENTS FOR LOCKOUT DEVICES Departments with departmental equipment subject to lock out tag out requirements shall be responsible for providing a sufficient number of lockout devices. Lockout devices shall: Be designated for exclusive use as energy source lockout devices, and cannot be used for other purposes such as securing toolboxes or lockers. Be standardized on the basis of color, shape, and/or size. Indicate the identity of the person applying the device. Be substantial enough to minimize early or accidental removal. Be accessible only by the designated employee to which it was issued through use of a specific key. Be removed only by the employee who placed them. See exception in Release From Lockout/Tagout section. Be removed upon completion of the work and after the installation of the protective guards and/or safety interlock systems. F. REQUIREMENTS FOR TAGOUT DEVICES Tags shall be used as a means to prevent accidental injury or illness to employees who are exposed to hazardous or potentially hazardous conditions, equipment, or operations which are out of the ordinary, unexpected, or not readily apparent. Tags shall be used until the identified hazard is eliminated or the hazardous operation is completed. Tags need not be used where signs, guarding, or other positive means of protection are being used. Tagout devices must include: a. A statement prohibiting unauthorized removal. b. A warning of the specific hazardous condition represented by the equipment to which they are attached, which shall be stated through the use of clearly understood legends such as “Do Not Operate,” “Do Not Close,” or “Do Not Start.” c. A signal word such as “Danger” or “Caution”. This shall be readable at a minimum distance of five feet and shall be understandable to all employees who may be exposed to the identified hazard. d. The reason for placing the tag, e. A major message indicating the specific hazardous condition or the instruction to be communicated to the employee. This shall be presented in either pictographs, written text, or both and shall be understandable to all employees who may be exposed to the identified hazard. All affected employees shall be informed as to the meaning of the various tags used throughout the workplace and what special precautions are necessary. f. The identity of the employee applying the tag. g. Information to contact the employee placing the tag. h. The date and time the tag was placed. Tagout devices shall be: a. Used in addition to locks. b. Removed only by the employee who placed them. See exception in Release From Lockout/Tagout section. c. Removed upon completion of the work and after the installation of the protective guards and/or safety interlock systems. d. Standardized on the basis of color, shape, size, print style and/or format. e. Affixed as close as safely possible to the hazards by a positive means such as string, wire, or adhesive that prevents their loss or unintentional removal. The means of attachment for tagout devices must meet the following criteria: a. Be able to be affixed by hand. b. Be non-reusable. c. Be self-locking with a minimum unlocking strength of 50 lbs. d. Be capable of withstanding the environmental conditions to which they are exposed. (Note: A simple device which meets these criteria is a one-piece nylon cable tie.) Workers must receive instruction on the following limitations and requirements of tags: a. They do not provide a physical restraint. b. They are little more than warning devices and may evoke a false sense of security unless their meaning is clearly understood. c. They must be legible and understandable by all employees. d. Both tags and attachment devices must meet certain requirements as specified in this section, and must be securely attached so that they cannot be inadvertently detached. e. Tags are not to be removed, bypassed, obscured, ignored or otherwise invalidated without proper authorization. G. USE OF BLOCKS Suitable blocks shall be used as safety devices for making a piece of equipment safe to be repaired or serviced. Blocks must be placed under any equipment that might move by sliding, falling, or rolling. Another form of blocking is the placement of a blind. A blind is a disk of metal placed in a pipe to ensure that no air, steam, or other substance will pass through that point if the system is activated. Before installing blinds or blocks the pressure must be released from steam, air, and hydraulic lines. Coiled springs, spring-loaded devices, or suspended loads must also be released so that their stored energy will not result in movement. H. PLANNING FOR LOCKOUT An initial survey shall be carried out to determine which switches, valves, or other energy isolating devices apply to the equipment being locked out. More than one energy source may be involved and shall be considered in the survey. See “Energy Control, Identification of Sources” section. Any questionable identification of sources shall be cleared by the employees with their supervisors. Before lockout is implemented, the supervisor must give job authorization. Only supervisors or authorized employees shall designate duties and responsibilities relating to the actual details of the lockout/tagout. Energy isolating devices shall be operated only by authorized employees or under the direct supervision of authorized employees. Where high voltages greater than 480V are involved, the electrician supervisor shall be responsible for turning off the main power controls. For complex systems, a written checklist shall be prepared for equipment access, lockout/tagout, clearance, release, and start-up. I. LOCKOUT/TAGOUT STANDARD OPERATING PROCEDURE Before any employee performs maintenance, repairing, cleaning, servicing, or adjusting on a machine where unexpected start up of stored energy could occur and cause injury, the machine shall be isolated. All energy sources which could activate the machine must be locked out. The authorized employee who turns off a machine shall have knowledge of the type, magnitude and hazards of the energy and the method to control the energy. The authorized employee shall notify all affected employees that a lockout is required and the reason. If applicable, there shall be coordination between affected departments. If the equipment is operating, it shall be shut down by the normal stopping procedure. The employee shall check to be sure that no one is operating the machinery before turning off the power. The machine operator shall be informed before the power is turned off. Personnel who are knowledgeable about the equipment operation including shut down and restart procedures shall be involved. The energy isolating device shall be operated so the energy source is disconnected from the equipment. Stored energy shall also be dissipated or restrained. For example, any mechanism under load or pressure, such as springs, shall be released and blocked and steam, air, and hydraulic lines shall be bled, drained, and cleaned out. The energy isolating device shall be locked and tagged out with an assigned individual lock. Tags shall be attached to the energy isolating device and to the normal operating control to prevent operation. All energy sources which could activate the machine shall be locked out. If more than one employee is required to lockout equipment, each employee shall place a lock and tag on the energy isolating device or a group lock out device can be used. A single lock may be used to lockout the machine or equipment with the key being placed in a lockout box or cabinet which allows the use of multiple locks to secure it. Each employee shall then use their own lock to secure the box or cabinet. As each person no longer needs to maintain their lockout protection, that person shall remove their lock from the box or cabinet. If a supervisor locks out equipment for an entire crew, they are responsible for carrying out all of the lock out procedures and informing the crew when it is safe to work on the equipment. The authorized employee shall ensure that no personnel can be exposed and check that the energy sources are disconnected by operating the normal controls to ensure that the equipment will not operate. If there is a possibility of re-accumulation of stored energy, then verification of isolation shall be continued until maintenance is complete. A qualified person shall use calibrated 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 de-energized and isolated. The main valve or main electrical disconnect must be tested to be sure that the power to the machine is off. All energy sources which could activate the machine must be locked out. The operating controls shall be returned to the neutral or off position. The equipment is locked out. Accident prevention tags shall be attached. No one shall remove the lock without proper authority. If there is a need to temporarily remove lockout/tagout devices for testing of the equipment as part of the repair or maintenance procedure after it is locked out, the following steps shall apply: a. Clear the equipment of tools and materials. b. Ensure that machine components are operationally intact, including guards. c. Clear personnel. d. Notify affected employees that lockout/tagout devices have been removed. e. Clear the locks and tags according to the established procedure in the Release From Lockout/Tagout section. f. Proceed with the test. g. Disconnect the energy source and lock and tag the controls to continue work. Care shall be taken to ensure that lockout/tagout information is transmitted between work shift crews. J. RELEASE FROM LOCKOUT/TAGOUT When the job is complete and equipment is ready for testing or normal service, an authorized person shall check the equipment area to see that no one is exposed. Nonessential items shall be removed and machine or equipment components including guards and safety devices shall be operationally intact. Defective guards shall be repaired or replaced before removing locks and tags. When equipment is clear, authorized employees shall remove all locks and tags using the correct removal sequence. As a general rule, no one shall remove a lock or tag except the person who applied the device. Exception: When the authorized employee who applied the lockout or tagout device (installer) is not available to remove it, that device may be removed under the direction of the installer’s immediate supervisor. If the lock is removed by someone other than the installer, safety equivalent to the original process of having only the installer remove the device shall be maintained. The specific procedure for removal of the lock shall include at least the following elements: a. Verification by the immediate supervisor that the employee who applied the device is not at the facility, b. Making all reasonable efforts to contact the authorized employee to inform them that his/her lockout or tagout device has been removed, and c. Ensuring that the authorized employee has this knowledge before they resume work at the facility. Affected employees shall be informed that the lockout/tagout devices have been removed. A visual check shall be made before restoring energy to ensure that everyone is physically clear of the equipment. The energy isolating device shall be operated to restore energy to the equipment after ensuring that no one is exposed. K. EMERGENCY LOCK REMOVAL The campus Lock Shop is the only authorized purchasing agent for locking devices. They will procure and provide any employee with a lock for use in a lock-out / tag-out situation. If it is determined that an emergency exists, and that a lock must be removed (pending determination of a safe environment), the campus lock shop can provide the necessary key for any lock. Should a dire emergency exist, and it has been determined that the environment is safe, a lock may be removed in any manner that will not constitute an un-safe situation.
	[top of page]	This page last updated May 21, 2008 Site contact: UCO Web Support