Lockdown

There are several definitions for the term lockdown, the most common of which pertains to a state of containment or a restriction of progression. A lockdown is an emergency protocol to prevent people or information from escaping, which usually can only be ordered by someone in command. Lockdowns are also used to protect people inside a facility or, for example, a computing system, from a dangerous external event.

There may be various levels of lockdown. For example, in the case of buildings, a partial lockdown means that the doors leading outside of the building are locked and people may not exit or enter the building. A full lockdown means that people must stay where they are and may not exit or enter a classroom, apartment unit, store unit, an office space, condo unit or the building. If people are in a hallway they must go into the nearest classroom, apartment unit, condo unit, office space or store unit.

In its most common usage in corrections units, the term lockdown can be defined as a course of action to control the movement of inmates. Confining all prisoners, except workers, to their cells until the end of the day is an example of a "lockdown period" in a corrections schedule. However a "full lockdown" is used when all prisoners are locked in their cells to prevent a riot or unrest from spreading or during an emergency.

In US guidelines, occasions for preventing entry into a hospital may include: power failure, earthquake, flooding, fire, bomb threat, hostage crisis and active shooter. Occasions for preventing both entry and exit from a hospital may include: external contamination, civil disturbance and abduction of an infant or child.

In manufacturing, the term lockdown event refers to a continuous improvement initiative in which manufacturing in a specific area (typically a cell or specific piece of machinery) is halted in order to contain, and determine, what are the issues that are preventing the manufacture of goods from meeting the quality specifications. During the lockdown event a multi disciplinary team reviews the specific area manufacturing processes, tooling and machine condition, to find the root cause(s) of the problem(s). Once changes to the process, or machine repairs that may include adjustments and/or replacement are effected, a sample run is initiated and evaluated. If the results of the validation are within the required specifications, the area lockdown is lifted and production is resumed. Follow up sampling is conducted subsequently to insure continuity of the lockdown results.

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Wikipedia