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 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 also known as "Hold and Secure" 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 a good 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 the United States, schools practice lockdowns in the wake of the Columbine High School massacre, when potential assailants possessing firearms (with a hostile intent) enter the school, or from internal events. It is considered an overreaction to lock down a school due to nearby criminal activity, such as a bank robbery, as criminals of that sort do not fit the profile of those who would take advantage of the perceived safety of a school (which, in reality, is a terrible place for refuge, as it is full of people in every room, all the time) and only rarely have such criminals entered a school while fleeing police.

In some schools (unlisted for certain reasons), a "non-aggressive" lockdown would mean that all students would follow school lockdown procedure, and a student locker drug search would be performed by either the school staff, a K9 (canine) unit, the local police, or all three. However, not every school practices this, and some will actively search all lockers without requiring a complete lockdown.

In American protest movements dating from the 1960s and 70s, the term lockdown applies to a person's attaching themself to a building, object, fence or other immobile object. This was originally done with chains and handcuffs, but other devices have been introduced, including tripods and tubes or pipes with handholds built in to link a person to an object or to create chains of people.