Stored Energy And Lock Out Tag Out Procedure
- Published: Wednesday, 28 November 2018 08:36
When machinery is shut down for maintenance or cleaning, energy within the system does not simply disappear. Stored energy can cause machinery to move unexpectedly, which can result in serious injury or fatality.
Often considered electrical, energy can be in many forms such as pneumatic, hydraulic and potential, and each type will require different methods for safe isolation.
It is a legal requirement to ensure the safe isolation of equipment to prevent injury in the workplace, and a commonly used method is Lock Out Tag Out Try Out or LOTOTO. This is the procedure whereby machinery is effectively ‘locked’ to prevent unauthorised or accidental restarting. The lock is then ‘tagged’ to communicate to others that the machinery has been shut down and by whom, this should be the only person who then removes the tag and the lock. The machinery is then tested during the ‘try out’ phase to see if there is any secondary energy present.
This Lock Out Tag Out procedure should be employed whenever maintenance or cleaning of equipment is required to ensure the safety of workers. Machinery should be effectively shut down at both the primary and secondary energy sources. Other workers should be made aware that this is taking place. After equipment has been safely shut down, the LOTOTO procedure should take place. Once any stored energy has been safely isolated, the tags and locks are in place securely, work can then take place. Other workers should also be made aware when the work is complete and the machinery will be restarted.
One Man One Lock
This safety first method paired with another proven method of ‘one man one lock’ can help minimise accidents. By attributing someone’s name to lock removes anonymity and adds accountability and further responsibility. Engraved safety padlocks which have the workers name on them or lockout tags with a photograph have been proved to be used in a more considered manner.
The one man one lock approach is now considered best practice during the safe isolation of systems. As modern plant will often require multiple people in the process of cleaning or maintenance, a group lock out procedure will be required to ensure the safety of everyone before re-energisation. Separate locks may also be required for contractors or cleaners on a temporary basis – signing this equipment in and out will prevent loss and allow them to fit in to the existing safe system of work.
Lockout equipment should always be kept on or near the isolation point and bespoke lockout stations are often created to ensure the equipment is obvious and always present.
It has been a common belief that safe isolation systems can slow down work, and pressures on a company for outputs can unintentionally put people in harm’s way as shortcuts are taken. A clear system of work which includes the safe isolation of equipment, and with ease of access to a lockout station, will soon become the norm. It is vital that safety equipment is not simply purchased for compliance, but is used correctly to ensure major incidents or accidents do not occur.
It is vital that stored energy is considered during the safe isolation of equipment to ensure the safety of workers. Paired with LOTOTO and One Man One Lock can further ensure that accidents in the workplace are minimised. Often a workplace will not have had an accident until a major incident occurs and with a safe system of work in place this can be prevented.