Presence protection
As presence protective devices that help you decide whose inhabitants (s) if they want to engage a person or not be referred to, and in a house. Presence protection is differentiated from burglary protection , devices that protect against an unnoticed break-in.
Presence protection includes:
All of the examples mentioned serve the timely detection of unwanted visitors. While the peephole and intercom system only help to assess or identify a visitor, the door chain also enables documents (e.g. ID papers) to be exchanged without having to open the door completely. In terms of stability, a door chain cannot keep up with the massive locking bracket of an additional or cross-bolt lock. In particular, when the box lock or the cross bolt are properly attached, opening the door forcibly, for example by kicking, is extremely difficult, which is rarely the case with door chains.