Digital Encyclopedia

Door Latch For Doors *** Applications: A. Security - Authorization/ID, Prevent Burglary Via lock picking , prevent robbery and other forms of theft B. Pets- Prevent lawsuits & legal liability claims for bites from pets C. Children - Prevent missing children and children who wander off **** Relevant Background: “A door chain, security chain, or security door chain consists of a small chain attached to the door frame, which attaches to a track on the door for security purposes. It is a type of lock that is often used along with other types of locks to secure a door... Door chains are mainly intended to allow a person inside a structure to open the door slightly for purposes of communicating with individuals outside or exchanging small objects through the door while still preventing the individuals outside from gaining unauthorized access into the structure...Door chains also can be set in place when the door does not need to be opened. They can only be touched from inside when t...

  Doors: Installation, Maintenance & Operating Mechanism *** Relevant Background on Doors:  " A  door  is a  hinged  or otherwise movable barrier that allows ingress into and egress from an enclosure. The created opening in the  wall  is a  doorway  or  portal . A door's essential and primary purpose is to provide  security  by controlling access to the doorway (portal).  Conventionally , it is a panel that fits into the portal of a  building ,  room , or  vehicle . Doors are generally made of a material suited to the door's task. Doors are commonly attached by hinges, but can move by other means, such as slides or counterbalancing... Doors may incorporate  locking  mechanisms to ensure that only some people can open them. Doors may have devices such as knockers or  doorbells  by which people outside announce their presence. Apart from providing access into and out of a space, do...