How to Choose the Right Safety Lockout Box?

Use this guide to match the hazardous energy source with an appropriate group lockout box and control method.
Workplace Hazard	Hazardous Energy or Source	Typical Equipment	When a Lockout Box Is Appropriate	Recommended Lockout Controls	Selection Considerations
Electrical energy	Electricity, including stored charge in capacitors and battery systems	Motors, control panels, switchgear, conveyors, battery-powered equipment	A qualified group needs to isolate one or more electrical disconnects and each worker must apply a personal lock.	Open the disconnect, verify absence of voltage, discharge stored energy, and secure the isolation point or key inside the box.	Choose a box with enough lock holes, durable insulation-resistant construction, and space for all isolation keys.
Mechanical movement	Rotating, reciprocating, cutting, crushing, or stored mechanical motion	Presses, mixers, saws, rollers, fans, robotic cells	Multiple workers or trades must control several disconnect points before entering a danger zone.	Stop equipment, isolate the prime mover, block or restrain moving parts, and test that motion cannot occur.	Select a box that can hold keys for every isolation device and can be clearly identified at the worksite.
Hydraulic pressure	Pressurized hydraulic fluid and pressure trapped in lines or accumulators	Hydraulic presses, lifts, injection machines, mobile equipment	A coordinated maintenance task requires isolation of pumps, valves, and other energy-isolating devices.	Shut down the pump, close and lock valves, bleed pressure, block elevated components, and verify zero pressure.	The box stores keys only; it does not replace valve locks, mechanical blocks, pressure gauges, or verification procedures.
Pneumatic pressure	Compressed air, gas pressure, and residual pressure in actuators or piping	Air cylinders, pneumatic tools, packaging machines, compressors	Several authorized workers need individual protection while working on the same pneumatic system.	Close and lock the supply valve, bleed residual pressure, secure moving parts, and confirm zero energy.	Use a box with sufficient capacity for valve-isolation keys and worker locks; verify compatibility with the site procedure.
Thermal energy	Steam, hot water, heated surfaces, refrigerants, or cryogenic materials	Boilers, ovens, heat exchangers, refrigeration systems, process piping	Multiple isolation points must remain secured while equipment cools, depressurizes, or is serviced.	Isolate fuel or power, close supply and return valves, drain or vent lines, allow safe cooling, and verify temperature and pressure.	Choose a weather-resistant box if used outdoors and keep it away from hot surfaces, steam, and corrosive atmospheres.
Chemical or process energy	Hazardous chemicals, process fluids, toxic gases, and residual chemical pressure	Pipelines, reactors, pumps, tanks, dosing systems	A maintenance team must control multiple valves or energy-isolating devices during a planned shutdown.	Isolate, drain, purge, flush, or blank the system as required; test for hazardous substances before work begins.	Use chemically resistant materials where necessary and keep the box outside the exposure zone.
Gravity and suspended loads	Potential energy from raised, suspended, or elevated components	Vehicle lifts, elevators, hoists, raised platforms, machine heads	The task involves several workers and requires control of both power isolation and physical supports.	Lower loads where possible, install rated blocks or pins, isolate the equipment, and verify stability before entry.	The box cannot prevent gravity hazards by itself; use approved blocking and support equipment in addition to lockout.
Multiple energy sources or complex systems	A combination of electrical, mechanical, hydraulic, pneumatic, thermal, or chemical energy	Production lines, automated cells, large process systems, facility utilities	A group lockout is needed to coordinate many isolation points, departments, or shifts.	Use a written energy-control procedure, place isolation keys inside the box, and require each worker to apply and remove a personal lock.	Prioritize capacity, visibility, portability, corrosion resistance, tamper resistance, and clear identification.