Fatalities and injuries from machines remain a high risk in many workplaces, especially during service and maintenance tasks when workers can be exposed to uncontrolled releases of energy after initiating a machine.
Analyses of incidents over past decades show that failure to lock out and tag out machinery or isolation areas is often a contributing factor. When machines are not properly locked or tagged, workers can be caught in moving parts, resulting in fractures, amputations, crushing injuries, or death.
When Lock Out/Tag Out Is Necessary
Employees should know the procedures, understand their importance, and recognize the consequences of noncompliance. Lock out and tag out procedures should be implemented in these situations:
- If an unexpected start-up of a machine would release stored energy.
- During all initial set-up procedures.
- When workers need to bypass or remove a safety device.
- When any body part must enter the danger zone or point of operation.
For employers creating or reviewing procedures, consider established program templates such as the Lockout Tagout Safety Plan for practical guidance on writing machine-specific controls.
Employer Recommendations
The primary responsibility for preventing machine-related injuries lies with the employer. To reduce risk and comply with OSHA, employers should take these actions:
- Ensure all workers clearly understand when hazardous energy control procedures apply.
- Provide training for energy control procedures.
- Develop and implement a written hazardous energy control program.
- Train employees on lock out and tag out protocols and required inspections before maintenance work begins.
- Label isolation devices clearly.
- Provide training in employees’ primary languages.
- Develop machine-specific lock out and tag out procedures.
- Provide sufficient lock out and tag out devices and necessary hardware.
- Do not allow workers under 18 to perform hazardous machinery work.
Employers looking for broader workplace-safety practices can also review resources such as Enhancing Workplace Safety and Health to align energy control with overall safety programs.
Worker Recommendations
Workers must follow their employer’s hazardous energy control procedures and report any program issues immediately. Complete all required training before performing maintenance or service.
- De-energize hazardous energy sources.
- De-energize electrical circuits.
- Block machine parts against motion.
- Shut down or disconnect motors and engines.
- Block flow of fluids in pneumatic or hydraulic systems.
- Lock out and tag out hazardous energy sources, including control valves and breaker panels.
- Dissipate or block stored energy.
- Block or release springs under tension or compression.
- Discharge capacitors.
- Avoid venting flammable, toxic, or explosive substances into the air.
- Vent permissible fluids from pressure tanks, vessels, or accumulators.
- Verify that all hazardous energy sources are de-energized before work begins.
- Use one key per lock and do not allow others to remove a lock that is not assigned to them.
- Ensure co-workers are clear of danger zones before re-energizing equipment.
- Inspect the work area and equipment before removing locks and returning equipment to service.
Manufacturer Recommendations
Manufacturers should design equipment to minimize the number of disconnection points and make required disconnection points easy to access. Equipment design should support safe lock out and tag out procedures and include optimal safety features for maintenance and repair.
Before implementing or changing a program, be sure to understand applicable regulations and insurance requirements. For assistance or to discuss how this applies to your operation, talk to an agent.
Frequently Asked Questions
What is lockout/tagout?
Lockout/tagout is a safety procedure that isolates energy sources and prevents accidental machine startup during maintenance or servicing.
Who must be trained on lockout/tagout?
Anyone who services, maintains, or operates equipment where hazardous energy control is required should receive training appropriate to their role.
Can I remove another worker’s lock?
No. Only the person who applied the lock should remove it, except in established emergency procedures defined by the employer.
How often should lockout/tagout procedures be inspected?
Periodic inspections are required to verify procedures are followed; employers should establish inspection frequency based on risk and regulatory guidance.