A machine-specific energy control procedure documents how to isolate and verify every energy source for one particular machine before servicing or maintenance. It identifies the machine, its hazards, the exact shutdown and lockout steps, how stored energy is made safe, and how workers verify isolation; it must reflect the machine as installed, not just a generic checklist.
What the procedure is for
Energy control, often called lockout/tagout (LOTO), prevents unexpected startup or the release of stored energy while people work on equipment. A procedure is “machine-specific” when it gives enough detail for an authorized worker to identify the correct machine and carry out the isolation steps without guessing. It is used for servicing and maintenance tasks where hazardous energy could cause injury.
Hazardous energy is not limited to electricity. Depending on the equipment, it can include mechanical motion, gravity, hydraulic or pneumatic pressure, steam, hot or cold materials, chemicals, and electrical energy stored in capacitors. A stopped machine is not necessarily a safe machine: its controls may still be energized, a suspended component may fall, or pressure may remain trapped.
In the United States, workplace lockout/tagout requirements are addressed by OSHA’s control-of-hazardous-energy standard, 29 CFR 1910.147. Applicable rules and procedures depend on the workplace and task. A written document supports, but does not replace, training, suitable locks and devices, safe work practices, and compliance with applicable requirements.
What a machine-specific procedure contains
A useful procedure is precise enough to distinguish the machine from similar equipment and to show where and how energy is controlled. It commonly records:
- Machine name, identification number, location, and the work or equipment covered.
- Each energy source, its type and magnitude where known, and the specific isolating device that controls it.
- The normal shutdown method, followed by the steps to operate each isolating device.
- How to apply personal locks and tags, and how to dissipate, restrain, block, or otherwise control stored energy.
- The method for verifying isolation before work begins, including a safe try-start or test where appropriate.
- How to restore the machine to service and account for workers, tools, guards, and affected employees.
Names and locations should be unambiguous. “Turn off the power” is inadequate if the machine has two disconnects, a shared supply, or a separate control circuit. A procedure should identify the actual device—for example, “disconnect DS-4 on the north panel”—and use a diagram or photograph when that helps workers find it.
How to develop and use it
- Inspect the machine and its energy paths. Review labels and available diagrams, then confirm the installation in the field. Identify every supply and potential source of motion or stored energy, including sources that may be hidden or shared with nearby equipment.
- Write the sequence in the order workers will perform it. Describe how to notify affected employees, shut down normally, isolate each source, apply locks and tags, and address residual energy. Specify waits or checks only when justified by the equipment’s design and hazards.
- Verify the result. After checking that people are clear, attempt the normal start control or use an appropriate test method to confirm the machine cannot operate. Return controls to off after a try-start. Electrical testing must be performed by qualified personnel using suitable methods and equipment; a control-panel indicator alone may not prove electrical isolation.
- Keep control during the work. Each authorized worker generally applies their own lock to each required isolation point or to a suitable group lockout arrangement. No one should rely on another person’s lock as their personal protection.
- Restore safely and document changes. Before removing locks and restarting, inspect the machine, replace guards, remove tools, confirm workers are clear, and notify affected employees. Follow the workplace’s established process for lock removal and restart.
For example, a conveyor might have electrical power, a pneumatic actuator, and a raised gate held by gravity. Switching off the motor does not address the actuator or the gate. The procedure needs to identify and isolate the relevant supplies, release or otherwise control pressure, and mechanically secure the gate before a worker enters the hazard area. The exact steps must be determined for that conveyor, not copied blindly from another one.
Template
| Field | Entry |
|---|---|
| Machine name, ID, and location | |
| Work covered and procedure revision/date | |
| Energy source and hazard | |
| Isolation device and exact location | |
| Shutdown and isolation sequence | |
| Stored-energy control method | |
| Verification method and result | |
| Restart and lock-removal steps | |
| Prepared/reviewed by and review date |
Sample (fictional): Machine: Line 3 belt conveyor, C-03, east work area. Source: electrical supply; isolator: disconnect D-03 beside the infeed. Stored energy: elevated guard; control: lower and secure it using the designated support. Verification: after locking D-03, check that the belt will not start using the normal start control, then return the control to off. This brief example is illustrative only; it is not a complete procedure for real equipment.
Review, exceptions, and common mistakes
Review the procedure when a machine, its controls, energy sources, or work methods change, and when an inspection or incident reveals a gap. A review should also confirm that device labels match the written steps and that workers can access the procedure where it is needed. Training should cover the specific hazards and the roles of authorized and affected employees.
Common errors include listing only the main electrical disconnect; confusing a stop button with an energy-isolating device; forgetting gravity, pressure, heat, or stored electrical energy; and treating a tag as a substitute for a lock where locks can be used. Another frequent weakness is vague verification language such as “make sure it is off.” State a practical method and its limits. Never assume that a machine is safe because a light is dark, a display is blank, or a motor has stopped.
Some equipment or tasks may qualify for a limited exception under applicable rules, but exceptions have specific conditions. Do not omit a procedure simply because a job is brief, a machine is small, or workers perform the task frequently. Have a qualified safety or engineering professional assess uncertain cases against the applicable requirements.
Frequently Asked Questions
Is a machine-specific procedure the same as a LOTO checklist?
A checklist may help workers follow the steps, but the procedure is the complete equipment-specific account of energy sources, isolation points, stored-energy controls, verification, and restoration. A generic checklist alone usually cannot tell a worker which device to operate on a particular machine.
Does every machine need its own procedure?
Not necessarily. Applicable rules may allow one procedure to cover a group of machines when they share the same energy-control methods and the procedure clearly identifies the equipment covered. Differences that affect isolation or verification must be addressed rather than assumed away.
Can a stop button or emergency stop replace lockout?
No. These controls generally stop operation but do not isolate energy. A machine may restart, remain energized, or retain stored energy. Use the energy-isolating devices and verification steps specified by the applicable procedure.
Who should write or approve the procedure?
It should be developed by people who understand the machine’s energy systems and the workplace’s energy-control requirements, with input from affected workers and relevant technical personnel. The employer is responsible for ensuring that the procedure and training meet applicable rules.
How often should a procedure be reviewed?
Review it when equipment or work changes, when a problem or incident exposes a weakness, and as part of required periodic inspections. The review schedule and inspection requirements should follow applicable regulations and the employer’s program.