Lock Out & Tag Out (LOTO)
What Does Lockout Tagout (LOTO) Mean?
Lockout/tagout (LOTO) is a set of procedures that are used to ensure that equipment is shut down, inoperable, and (where relevant) de-energized. This allows maintenance and repair work on the system to be performed safely.
Any workplace scenario involving equipment that could lead to the inadvertent release of hazardous energy requires the use of lockout/tagout procedures. In this context, "hazardous energy" includes not only electricity but other forms of energy such as pneumatic pressure, hydraulic pressure, and gas. The purpose of LOTO procedures is both to prevent direct exposure to this energy, as well as to prevent harm caused by any machinery or objects that could be moved by that energy (e.g., a pneumatic press accidentally being activated).
The Importance of Lockout/Tagout Procedures
The use of lockout/tagout procedures is considered a critical aspect of workplace safety in any occupational setting in which workers come into direct contact with machinery or workplace equipment.
When machines or equipment are being prepared for service or maintenance, they often contain some form of "hazardous energy" that can cause harm to people in the area. When we talk about hazardous energy, we mean any type of energy that can be released and might harm a person. This could include energy of the following types,
- Chemical
- Electrical
- Hydraulic
- Mechanical
- Pneumatic
- Thermal
Without the use of proper LOTO safety procedures, the serviced equipment can unexpectedly start up or otherwise release these forms of energy. This can lead to injuries and even death to the people working on the machine and even to others working in the area or living in the community.Accidents which can be prevented by LOTO procedures include,
- Electrical accidents
- Crushing
- Lacerations
- Fires and explosions
- Chemical exposure
LOTO Procedures
The specific actions for applying LOTO will differ from equipment to equipment, and from facility to facility. The general LOTO procedure should follow a basic 6 step process.
1. Prepare for Shutdown
Notify affected employees that maintenance will be performed under LOTO. The authorized employee should review the hazards and LOTO procedures for the equipment that will be serviced.
2. Shutdown Equipment
The authorized employee will shut down the equipment following company and/or manufacturer's requirements.
3. Isolate Equipment
Isolate the equipment from the hazardous energy sources using the equipment specific LOTO procedure.
4. Place Locks and Tags
Locks and/or tags should be placed on valves, breakers/electrical disconnects, blank flanges, and any other point called out on the equipment specific LOTO procedure.
5. Release/Block Stored Energy
Release stored energy from the stored energy hazards identified in the LOTO procedure, such as releasing springs, blocking elevated parts that could drop, stopping moving parts, draining fluids, venting gases, etc.
6. Verify Equipment Isolation
Confirm that workers are clear from the area, locking devices are securely in place, and that the equipment is isolated. Once this is done, attempt a normal start-up to confirm that the equipment does not start.