Lock Out/Tag Out programs are used to prevent contact with a hazard while performing tasks that require the removal, by-passing, or deactivation of safeguarding devices, and the unintended release of hazardous energy (stored energy), or the unintended start-up or motion of machinery, equipment, or processes.
Lock Out is the control of hazardous energy by the placement of a lock or tag on an energy-isolating device, indicating that the energy-isolating device is not to be operated until removal of the lock or tag.
In practice, lockout is the isolation of energy from the system (a machine, equipment, or process) which physically locks the system in a safe mode. The energy-isolating device may be a manually operated disconnect switch, a circuit breaker, a line valve, or a block. Push buttons, selection switches and other circuit control switches are not considered energy-isolating devices.
Tag Out is a labelling process that is always used when lockout is required. The process of tagging out a system involves attaching or using a standardised label that includes the following information:
• Why the lockout or tag out is required (repair, maintenance, etc.);
• Time of Application of the lock or tag; and
• The name of the authorised person who attached the tag and lock to the system
Only the authorised individual who placed the lock and tag onto the system is the one who is permitted to remove them. This procedure helps make sure the system cannot be started up without the authorised individual’s knowledge.
Procedures should be developed in consultation with all stakeholders and involve the input of suitably qualified persons where necessary. The steps of a LOTO work instruction include:
1. Preparation for shutdown
2. Notification to all affected stakeholders
3. Equipment shutdown
4. Isolation of the system for hazardous energy
5. Dissipation of residual or stored energy
6. Lockout/Tag out
7. Verify Isolation
8. Perform Maintenance or Service Activity
9. Remove Lockout/Tag out devices
All employees and contractors must be trained in the LOTO program. The LOTO procedure should be available to all persons that may be affected by the isolation of the equipment or processes. This can be achieved through inductions, toolbox meetings and staff training sessions.