Lock-out/Tag-out Table of Contents
Applying Energy Controls
- Before Lock-out/Tag-out is applied, all employees who work in the affected area must be notified.
- Before starting work on any circuit, machine, belting, shafting, valve, or other apparatus which is out of service, employees shall assure themselves that a approved Lock-out device or Tag-out tag is properly attached to the apparatus control.
- Locks and tags by themselves do not de-energize equipment. Attach them only after the piece of equipment in question has been isolated from its energy sources.
- The OSHA regulation requires that control of hazardous energy be done according to a 6-step procedure.
- Preparation for Shutdown: Before you turn off any equipment in order to lock or tag it out, you must know:
- The types and amounts of energy that power it.
- The hazards of that energy.
- How the energy can be controlled.
- Equipment Shutdown:
- Shut the system down by using its operating controls.
- Follow whatever procedure is right for the equipment, so that you don’t endanger anyone during shutdown.
- Equipment Isolation:
- Operate all energy isolating devices so that the equipment is isolated from its energy sources.
- Be sure to isolate all energy sources – secondary power supplies as well as the main one.
- Never pull an electrical switch while it is under load.
- Never remove a fuse instead of disconnecting.
- Applying Lock-out/Tag-out Devices:
- All energy isolating devices are to be locked, tagged, or both.
- Only the standardized devices supplied by your supervisor are to used for lock-out/tag-out, and they are not to be used for anything else.
- There should be just one key for each lock. If the lock was supplied with more than one key, all extra (more than one) keys should be destroyed.
- Use a lock-out device if your lock cannot be placed directly on the energy control.
- When lock-out is used, every employee on the work crew must attach his/her personal lock.
- More than one employee can lock out a single energy isolating device by using a multiple-lock hasp.
- For large jobs, a lock-out box can be used to maintain control over a large number of keys.
- If tags are used instead of locks, they must be attached at the same point that you would attach a lock, or as close as possible.
- Tags must be filled out completely and correctly.
- Control of Stored Energy:
- Take any of the following steps that are necessary to guard against energy left in the equipment after it has been isolated from its energy sources.
- Inspect the system to make sure all parts have stopped moving.
- Install ground wires.
- Relieve trapped pressure.
- Release the tension on springs, or block the movement of spring-driven parts.
- Block or brace parts that could fall because of gravity.
- Block parts in hydraulic and pneumatic systems that could move from loss of pressure. Bleed the lines and leave vent valves open.
- Drain process piping systems and close valves to prevent the flow of hazardous materials.
- If a line must be blocked where there is no valve, use a blank flange.
- Purge reactor tanks and process lines.
- Dissipate extreme cold or heat, or wear protective clothing.
- If stored energy can re-accumulate, monitor it to make sure it stays below hazardous levels.
- Take any of the following steps that are necessary to guard against energy left in the equipment after it has been isolated from its energy sources.
- Verifying Isolation of Equipment:
- Take any of the following steps that fit your equipment and energy control program.
- Make sure all danger areas are clear of personnel.
- Verify that the main disconnect switch or circuit breaker can’t be moved to the on position.
- Use a voltmeter or other equipment to check the switch.
- Press all “start” buttons and other activating controls on the equipment itself.
- Shut off all machine controls when the testing is finished.
- Take any of the following steps that fit your equipment and energy control program.
- Preparation for Shutdown: Before you turn off any equipment in order to lock or tag it out, you must know:
Performing the Work
- Look ahead, and avoid doing anything that could re-activate the equipment that has been locked out.
- Don’t bypass the lock-out when installing new piping or wiring.
Removing Lockout/Tagout
- Make sure the equipment is safe to operate.
- Remove all tools from the work area.
- Be sure the system is fully assembled.
- Safeguard all employees.
- Conduct a head count to make sure that everyone is clear of the equipment.
- Notify everyone who works in the area that lock-out/tag-out is being removed
- Remove the lock-out/tag-out devices. Each lock-out device must be removed by the person who installed it (except in emergencies).
- A Lock-out device, Tag-out tag, or similar device, that has been placed for the protection of workers shall be removed only by the person in whose name it was placed and then only after the work has been completed and all workmen and tools are in the clear.
- In some workplaces, the last person to remove his lock may have extra duties.
- He/she may have to remove the hasp and lock-out device.
- Any tags should be removed, signed, and turned in to your supervisor.