Lock out tag out (or lockout-tagout) is a system often used in industrial premises and research establishments which employ potentially dangerous machinery. Its purpose is to ensure that equipment, which for any reason has to be temporarily or permanently decommissioned, cannot be restarted until all appropriate procedures have been carried out, and verified by every person, department, or agency responsible.
Lock Out or Tag Out?
A lock out system is generally used in conjunction with tag out. A machine or device is secured, with a locking device such as a hasp and padlock, so that it cannot be switched on or operated. The locking equipment may require several keys belonging to different responsible parties. Tag out is the administrative procedure by which equipment is labelled, usually with a specifically-designed tag, by the person responsible, to indicate that it must not be used or restarted. The difference between lock out and tag out is that in the case of tag out, the equipment may not be rendered physically incapable of operation, and the tag therefore serves as a warning instruction only. Obviously, the most fail safe option is when lock out and tag out are combined; equipment is both secured against restarting, and labelled so that responsible parties, and the procedures to be followed before recommissioning, are clearly identified.
How Lock Out Tag Out Works
Modern industrial equipment is usually designed so as to enable a lock out system to be installed. Valves and switches are often fitted with aligned holes through which a locking device can be passed. This may be a single padlock, but where a number of different operatives, contractors, or departments are involved, it is common to use a scissor clamp with six or more holes, each of which can take a contractor’s individual padlock. The equipment cannot be restarted until every padlock has been removed, thus ensuring that the assent of all parties has been obtained. Obviously, in such circumstances the tag system needs to be clear and well regulated, with the identity and purpose of each lock specified. It is usual for policies to be in place specifying when and by whom locks and tags can be removed; for example, the employer’s lock may be the last to be removed, and sometimes it is ruled that a tag can only be removed by the person who affixed it.
Why Lock Out Tag Out is Important
Industrial, construction, and scientific processes are often complex and may involve large numbers of people. Often, the equipment requiring isolation, whether for maintenance, repair, or decommissioning, may be physically remote from some of its elements, and it may not be apparent that isolation is intended or necessary. An efficient lock out and tag out system is vitally important to protect the public, workers, and equipment from the electrical or mechanical hazards of accidental or untimely restart.
Installing Lock Out Tag Out
The kit necessary to put a lock out tag out system in place is readily available, and not necessarily expensive. However, national, international, and industry-specific safety regulations can all be involved, and for this reason, unless the application is a very simple one, specialist advice is probably a good idea.