A school lock down is a procedure that is initiated when school officials believe that there is a credible threat to student and staff safety. Lock downs are classically used to protect students from school shooters, bomb threats, and other forms of violence, but they can also be used when police are engaged in an operation nearby, or when a national disaster has been declared. The goal is to keep students and staff safe, and while it may be frightening or disruptive, it is important for everyone to comply with the lock down for safety reasons.
When a lock down is ordered, people are told to stay inside their classrooms and lock the doors. This is designed to prevent anyone from entering the rooms from hallways and corridors. Windows will also be shut, locked, and covered with blinds to obscure visibility, and people are often encouraged to stay away from doors and windows, sheltering in an area where they cannot be seen.
The school itself will also be locked to prevent people from entering or exiting the building until the lock down has been lifted. In the case of precautionary ones, such as those that are initiated while police attempt to round up a suspect or serve a warrant, the lock down will be cleared as soon as the threat is over. In cases like bomb threats, police officers need to clear the school. A lock down may also be changed to an evacuation order if school officials feel that students and staff would be safer outside, or in the wake of a national disaster, once transport has been organized for the students and staff.
Lock down announcements are commonly made over public address systems, and in schools where the classrooms have phones, the phones will ring to alert teachers to a lock down. Some schools also send text messages to students and parents to alert them to the action, so that students who are not on-site know that it is not safe to return to school. This type of alert is very common on college campuses, letting students know that they should stay where they are rather than moving around on campus.
People are usually instructed to avoid using cell phones during a school lock down so that they do not clog the phone network. They are also usually ordered to remain as quiet as possible and to avoid engaging with anyone who is unknown, with the exception of clearly identified police, firefighters, and other emergency personnel. While the situation may distress parents, they should stay away from the school until the lock down has been lifted so that they do not interfere with emergency responders or police operations.