Typical Lockout Tagout Procedures

Electrical Energy

• When establishing lockout tagout procedures for electrical energy, it is important to know the potential sources. For most machines and equipment, the electrical energy flows through a circuit breaker of some sort. This is the location where the lock can be placed to prevent electrical energy from flowing into the machine.

Common LOTO Procedures:

• In some cases, simply unplugging the machine and applying the lock there can be effective. For heavy machinery, however, this is often difficult or impossible due to the size of the electrical cables. Start by determining every potential source of electrical energy and then determine exactly where and how the energy can be removed and secured.

Mechanical Energy

• Mechanical energy is often overlooked when working on machines and it can be quite dangerous. This type of energy is created through the motion of an object. In the context of a lockout tagout system, mechanical energy may become an issue if an employee working on a machine bumps a movable part, causing it to pick up momentum and become dangerous.

LOTO Procedures:

• Locking robot arms, movable saw blades, crushing parts, and anything else that moves is a good way to reduce any risk from mechanical energy. It is important to ensure things don't move unexpectedly and prevent mechanical energy from being released inadvertently from a bump or other event.

Hydraulic Energy

• Machines often operate using hydraulic energy as it can be extremely effective for heavy machinery. If the hydraulic oils are under pressure when someone is working on a machine, the potential is there for it to become released, causing the machine to activate. In some cases, the hydraulic oil is kept under pressure with electrical brakes, which will disengage when the power is cut.

LOTO Procedures:

• If a machine uses hydraulic energy of any type, part of the lockout tagout procedure should involve checking to ensure the energy has been released before working on the machine. It is not acceptable to enter a potentially dangerous area when there is energy like this built up, even if it is not likely to be released.

Pneumatic Energy

• Another type of energy to be aware of is pneumatic energy. It is somewhat similar to hydraulic energy, except it is formed using pressurized air. Some machines use pressure tanks to build up energy in the machine before it is needed. If a machine utilizes pneumatic energy for any purpose, a lockout tagout procedure should always include the discharging of pneumatic energy before beginning a job.

LOTO Procedures:

• To make sure that there is no stored energy within a pneumatic powered machine the maintenance worker may perform a test by trying to operate the machinery after it has been locked out. This should only be done after ensuring everyone involved in the maintenance is well away from the area before the test occurs. The gauges should indicate zero pressure upon a successful test.

Chemical Energy

• This energy can be stored and released through chemical reactions. Whether this occurs due to the mixing of two or more chemicals, a change in temperature of chemicals, a change in pressure, or any number of other situations, it is a concern.

LOTO Procedures:

• One of the most common examples of chemical energy includes the burning of gasoline in internal combustion engines. When dealing with lockout tagout systems, there may be a diesel generator providing backup power that would need to be removed and locked out. Identifying all potential sources of chemical energy in a machine and removing or securing them is essential for a good lockout tagout program.

Thermal Energy

• Thermal energy is energy in the form of heat. This could be heat from the sun, from the burning of something, or a number of other things. Modern machines don't often directly use this type of energy, but it is a good idea to be aware of it. If a machine can become active from thermal energy, it too must be removed and secured before any work can begin.

LOTO Procedures:

• One of the best routes for protecting employees from this type of hazardous energy is to check and see if the machine becomes hot when it has power.

Notification

• All employees who work with or around a machine should be notified of any scheduled maintenance.

Visual Communication

• Put up signs, cones, safety tape, or other forms of visual communication to let people know that a machine is being worked on.

Energy Identification

• All sources of energy should be identified prior to creating a lockout tagout procedure. The procedure should account for every possible energy source.

How Energy Is Removed

• Determine exactly how the energy should be removed from the machine. This could be simply unplugging it or tripping the circuit breaker. Choose the safest option and use that in the procedure.

Dissipate Energy

• After energy sources have been removed, there will be some amount left in the machine in most cases. "Bleeding off" any remaining energy by attempting to engage the machine is a good practice.

Secure Movable Parts

• Any parts of the machine that can move and result in injury should be secured in place. This can be done through built-in locking mechanisms or finding alternative ways to secure the parts.

Tag/Lock Out

• All employees who will be working on the machine must individually apply a tag or lock to the energy sources. Whether it is just one person or many, it is essential to have one tag for each person working in a potentially dangerous area.

Engagement Procedures

• Once the work has been completed, procedures should be in place to confirm all employees are in a safe location and that any locks or safety equipment have been removed before powering the machine up.

Other

• Taking any additional steps to improve the safety of this type of work is very important. All workplaces should have their own unique set of procedures that apply to their specific situation.

Retraining for these procedures should take place when employees have:

• Different job assignments

• A change in energy control procedures

• A new machine or process that presents new hazards.