Lockout/Tagout for Non-Electrical Hazards: Energy Control
Overview
Lockout/tagout procedures for non-electrical hazards control pneumatic, hydraulic, mechanical, thermal, and chemical energy sources that can cause injury during maintenance or servicing.
Why This Is Important
Non-electrical energy sources can be just as dangerous as electrical hazards, causing severe injuries through unexpected machine startup, pressure release, or exposure to stored energy.
Hydraulic and pneumatic systems can maintain pressure long after shutdown, while mechanical systems may have stored energy in springs, counterweights, or rotating components.
Best Practices & Safety Tips
Identify Energy Sources
Identify all non-electrical energy sources including pneumatic, hydraulic, mechanical, thermal, and chemical systems before beginning work.
Apply Individual Locks
Apply individual locks to energy isolation devices — never share locks or rely on others' lockout devices. Each worker uses their own lock.
Use Identification Tags
Use tags to identify the purpose of lockout and contact information for the person who applied it. Tags provide critical information.
Verify Isolation
Verify isolation by attempting normal startup procedures after lockout is applied. Ensure all energy sources are controlled.
Energy Source Types and Controls
Pneumatic Systems
- Shut off air supply at main valves or compressor
- Bleed residual pressure from lines and components
- Lock out air supply valves to prevent re-pressurization
- Verify zero pressure with gauges before beginning work
Hydraulic Systems
- Isolate hydraulic pumps and power units
- Relieve system pressure through designated relief valves
- Block cylinders to prevent movement from residual pressure
- Allow systems to cool if operating at high temperatures
Mechanical Energy
- Block or secure components that could move due to gravity or stored energy
- Release spring tension in controlled manner using proper procedures
- Secure counterweights and rotating components
- Chock wheels and secure mobile equipment
Thermal Energy
- Allow heated systems to cool to safe temperatures before beginning work
- Isolate steam and hot water lines with proper valve lockout
- Use temperature monitoring to verify safe working conditions
- Provide cooling time for systems that retain heat
Lockout Procedures
Preparation Phase
- Follow established procedures to shut down and isolate each energy source
- Notify affected personnel of planned maintenance activities
- Gather required lockout devices and personal protective equipment
- Review energy isolation points and procedures
Isolation Phase
- Shut down equipment using normal operating procedures
- Isolate all energy sources at designated isolation points
- Apply lockout devices to prevent re-energization
- Test isolation effectiveness before beginning work
Verification and Work
- Attempt normal startup to verify effective isolation
- Begin maintenance work only after verification is complete
- Maintain lockout throughout the entire work period
- Test equipment function before removing lockout devices
Discussion Questions
- Energy Identification: What non-electrical energy sources exist in your work area that require lockout procedures?
- Verification Methods: How do you verify that all energy sources have been properly isolated before beginning work?
- Safety Violations: What would you do if you discovered equipment that wasn't properly locked out during maintenance?
- Multi-Person Lockout: How do you handle situations where multiple people are working on the same equipment?
- Complex Systems: What challenges exist in identifying and controlling all energy sources on complex equipment?
Remember: Non-electrical energy sources pose serious hazards that require the same rigorous lockout/tagout procedures as electrical systems. Proper energy isolation protects against unexpected equipment startup and energy release that can cause severe injuries or death. Never remove another person’s lockout devices — only the person who applied them may remove them.