Another form such legislation sometimes takes is in the creation of a perimeter around a facility, known variously as a "buffer zone", "bubble zone", or "access zone". This area is intended to limit how close to these facilities demonstration by those who oppose abortion can approach. Protests and other displays are restricted to a certain distance from the building, which varies depending upon the law, or are prohibited altogether. Similar zones have also been created to protect the homes of abortion providers and clinic staff.