Isolation Procedures such as Lockout and Tagout (LOTO) processes are vital for protecting the safety of operatives and for protecting investments made in machinery and other equipment.
Isolation Procedures are often seen as a technical process. Something that can be seen as part of risk assessment simply to be followed up afterwards as an operational control. In practice, LOTO processes are documented stages that must be practically applied in sequence to assure the safety of the people directly and indirectly involved with the work, protect the structure and equipment from damage or destruction.
What is Lock Out – Tag Out?
Lockout and Tagout is a system or protocol for isolating energy sources before the inspection and maintenance of equipment. Designed to prevent accidents and prevent unplanned damage to machinery and the processes it supports.
Depending on the circumstances, LOTO prevents operation of such equipment whilst it is under repair, out of commission or where it is only for use for certain groups or shifts. It can also be used to prevent the accidental use of such equipment or unauthorised staff from operating it.
LOTO can encourage wider safe operating procedures; because LOTO will require a clearly defined protocol, staged from shutdown through to maintenance, this can encourage a review of the safe systems of work present at each stage of the process.
A recommended staged process is as follows:
- Prepare for shutdown
- Inform employees
- Turn off equipment
- Isolate energy sources
- Perform maintenance
- Test all circuits
- Test the equipment controls
- Lock off switches.
Specific circumstances may need to be adapted from the above. The importance of a safety process, effective communication, competence and awareness of all energy and feedstock sources are vital.
Types of Equipment
Lock Out – Tag Out solutions fall into the following broad categories.
- Conventional lock boxes and bags. These can used to store safety critical equipment at site level with access only to authorised persons – in remote locations this may include storage of the LOTO equipment. Locking such equipment away minimises the risk of it being used by unauthorised personnel who have not, perhaps, properly isolated the equipment
- Lockout devices. These can physically isolate the equipment, preventing the start-up, movement, or flow. Examples include electrical lock out, value lock outs, cable lock out and cylinder lock outs. They can be designed for the specific machine concerned or be more generic, and specialist advice needs to be taken in selection.
- Padlocks, hasps, and ties. In addition to specific lock out devices, padlocks, hasps, and ties can be used in several scenarios, often with accompanying tags,
- Tags and signs. These provide information to employees and record key facts such as when the lock out took and by whom. These can be colour-coded especially where is there is more one lock out authority, i.e. different staff doing their own maintenance regimes on the machine concerned.
Safe systems of work should never be assumed. Implementing Isolation, Lock Out -Tag Out procedures may highlight other areas of improvement within the safety process.
