Failure to de-energize equipment leads to a tragic outcome
In January 2023, an employer received a citation with proposed penalties of $145,027 for allegedly failing to de-energize electrical equipment. If you operate or use machinery or equipment to which lockout/tagout is applied, or work is an area where lockout/tagout is performed, you need to understand the following:
- Procedures involved in lockout/tagout,
- Reasons for lockout/tagout, and
- Dangers involved when interfering with lockout/tagout.
In the above incident, an employee was exposed to an arc flash, arc blast, smoke inhalation, and electrical hazards while working in an electrical vault. The employee suffered severe burns, later succumbing to his injuries. Another employee re-energized electrical equipment while the employee was inside of the vault without proper personal protective equipment.
What is involved in the procedure?
The procedure contains steps for shutting down, isolating, blocking, and securing machines or equipment to control hazardous energy. An orderly shutdown must be used to avoid any additional or increased hazards when the equipment is stopped.
Each piece of equipment or machine needs its own lockout/tagout procedure, which contains the steps for shutting down, isolating, blocking, and securing machines or equipment to control hazardous energy.
As with the incident above, employers must also review the associated manufacturer’s bulletins and adhere to the manufacturer’s safety recommendations while performing service or maintenance activities. The procedure also includes steps for testing and verifying the effectiveness of the lockout/tagout devices and other energy control measures.
If you have workers who face electrical hazards during servicing or maintenance activities, ensure they have training as required by the electrical safety standards. Training as an authorized employee under the lockout standard isn’t enough when electrical energy is a hazard.
Workers who perform lockout/tagout require training as authorized employees under the standard. However, an authorized employee can not verify that an electrical circuit is de-energized. Doing so requires training as a qualified person.
The electrical standards require that a qualified person verify, using test equipment, that the circuit elements and equipment parts have been de-energized. Whether a person is qualified depends on the circumstances and the equipment involved. It is possible for an individual to be “qualified” on certain equipment in the workplace but “unqualified” on other equipment.
The de-energizing procedure
Every power source has its own procedure for lockout. Lockout may be accomplished by pulling a plug, opening a disconnect switch, removing a fuse, closing a valve, bleeding the line, or placing a block in the equipment.
Only the authorized person can perform these:
- Prepare for shutdown.
- Shut down the machine by following the normal method for shutdown.
- Isolate equipment from all energy sources and notify affected employees.
- Using unique locks, lock out all the energy sources involved.
- Release and/or relieve all sources of stored energy.
- Verify machine has been isolated and de-energized.
The employer discussed in the incident above didn’t de-energize electrical units while performing major maintenance. Alternatively, based on the calculated incident energy, the employee in the electrical vault should have been provided with the appropriate PPE for the environment.
Failing to de-energize equipment during servicing or maintenance activities could put your employees at risk for serious injury. Proper training, following your LOTO procedures, and performing periodic safety inspections can help prevent accidents and keep employees safe.
Key to remember
Suppose workers operate or use machinery or equipment to which lockout/tagout is applied, or work is an area where lockout/tagout is performed. In that case, they need to understand the procedures involved in lockout/tagout.