Workers servicing or maintaining machines or equipment can be seriously injured or killed if hazardous energy is not properly controlled. Injuries may include electrocution, burns, crushing, cutting, lacerating, amputating, or fracturing body parts. Anyone doing machine service, maintenance, or repairs needs to be trained as an authorized employee under OSHA’s lockout/tagout (LOTO) standard at 1910.147.
Authorized employees must know how to follow LOTO procedures so that machines and equipment cannot start unexpectedly to cause injury. This training outline focuses on the basic training requirements for authorized employees. (If employees are exposed to electrical hazards due to exposed electrical parts, follow the provisions for locking and tagging electrical circuits in 1910.333.)
To complete your training program, familiarize authorized employees with the equipment-specific procedures they are to use in your workplace.
- Introduce the terms used in LOTO procedures.
Lockout means applying a lock on a switch, valve, or other energy-isolating device to keep energy from flowing to the machine or equipment.
Tagout means applying a warning tag to an energy-isolating device that is not capable of accepting a lock. Tagout doesn’t provide the same degree of protection as lockout.
An energy-isolating device is a mechanical device that physically prevents the transmission or release of energy. Examples include circuit breakers, disconnect switches, or line valves. Push buttons, selector switches, and other operating controls are not energy-isolating devices.
An authorized employee does the service or maintenance work that’s covered by the LOTO standard. Each authorized employee applies his or her locks (or tags) to the equipment. If an affected employee is assigned to do covered service or maintenance work, he or she becomes an authorized employee.
An affected employee uses or operates equipment that can be locked or tagged out or works in an area where LOTO is used.
- Explain the limited roles for affected (and other) employees.
Affected employees need to recognize LOTO equipment and have a basic understanding of the procedures, but they do not do service, repair, or maintenance work. Affected employees must be notified about LOTO events, both before the locks or tags are applied to the energy-isolating devices and after they are removed.
All other employees whose work operations are or may be in an area where LOTO procedures may be used need to be instructed about the procedures. They must also be told that they are prohibited from attempting to restart or re-energize machines or equipment that are locked or tagged out.
- Outline the training needs for authorized employees.
After training, authorized employees must be able to:
- Describe the type and magnitude of the energy available in the workplace,
- Recognize applicable hazardous energy sources,
- Explain the methods and means necessary for energy isolation and control, and
- Perform LOTO procedures.
- Provide information on the available energy sources in your workplace.
Equipment can be powered by electrical, mechanical, hydraulic, pneumatic, chemical, thermal, or other energy sources. Each machine has one or more energy sources. Employees must know the types of energy the equipment uses and how much energy is available to the machine before a LOTO procedure can be started. The equipment’s LOTO procedures can describe energy sources by their types and magnitudes.
- Explain when to use lockout.
LOTO procedures isolate the machine from its energy sources. When authorized employees lock out equipment, they have control over the machine’s energy supplies.
If an energy-isolating device can be locked out, use lockout. New equipment, and equipment that has had a major repair, renovation, or modification since 1990, must have energy-isolating devices that are designed to accept a lockout device. If the equipment can be locked out, you can only use tagout if you can show that the tagout program provides as much employee protection as a lockout program would. This would include taking additional safety measures such as removing a fuse, valve handle, etc., so that the risk of accidental activation is minimized.
- Discuss the use of tagout.
If an energy-isolating device is not capable of being locked out, a tagout system must be used. When tagout is used, authorized, affected, and other employees must know that tags:
- Are essentially warning devices; they do not provide the same physical protection as a lock;
- Should never be removed, bypassed, or ignored;
- May evoke a false sense of security. Everyone must understand their meaning for them to be effective; and
- Have certain requirements for strength and durability.
- List the basic steps for applying LOTO.
The energy control procedures will be different for each type of machine. LOTO procedures must include the following steps, to be followed in order:
1) Prepare for shutdown. Review the equipment’s energy sources, identify energy-isolating devices, and make sure affected employees have been notified.
2) Shutdown of machine or equipment. Follow the formal operating procedures to turn off the machine.
3) Isolate the machine or equipment. Operate each energy-isolating device to stop the flow of energy to the machine.
4) Apply LOTO devices. Apply your lock(s) to the energy-isolating device(s). If you have to use tagout, apply tags to the energy-isolating devices, and take any additional safety measures, as applicable.
5) Release stored energy. For example, drain pressure from lines, insert blocks to keep elevated parts stable, etc.
6) Verify isolation of equipment. Try to turn on the machine at its control panel, check the readings on pressure gauges, etc.
- Outline the steps for releasing the equipment from LOTO.
When the repair, servicing, or maintenance work is done:
1) Make sure the machine is operationally intact (clear of tools and other materials, guards are in place, etc.).
2) Make sure employees are in safe areas.
3) Remove the lock(s) (or tag(s)).
4) Notify affected employees that locks (or tags) have been removed before the equipment is started.
- Discuss LOTO inspections and other provisions in your energy control program.
LOTO procedures must be periodically inspected (at least annually). The inspection process consists of having the authorized employee who normally uses the procedure lock out the machine. He or she is observed by another authorized employee (called the inspector) who typically doesn’t lock out that machine. This inspector reviews the procedure with the authorized employee to determine that he or she understands and follows all the steps in the procedure.
The goal is to be sure authorized employees are following the procedures and that the procedures themselves are adequate.