A door loop or door cord [1] is a mechanical device which provides a robust guideway for cabling between a swing door (the "door leaf") and a door frame.
Door loops are described in the NFPA 80 standard for fire doors. [1] [2]
Door loops are used in cases where electrical components are mounted in the door leaf, like for example a motorized door lock, smart lock, smart doorbell or solenoid bolt. Since the hinges move during operation, a normal laying of cable would quickly wear out. The door loop also ensures that the twisting of the cables is distributed over a longer cable length, which is decisive for the wear of the cables.
Normally, the door loop is mounted inside the door frame ("concealed door loops"), and can not be seen except for when the door is open. Another type is surface mounted transfers which serve the same function ("visible door loops"), which normally can be seen on the top of the door at all times.
A door is a hinged or otherwise movable barrier that allows ingress (entry) into and egress (exit) 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 doorway of a building, room, or vehicle. Doors are generally made of a material suited to the door's task. They are commonly attached by hinges, but can move by other means, such as slides or counterbalancing.
A firewall is a fire-resistant barrier used to prevent the spread of fire. Firewalls are built between or through buildings, structures, or electrical substation transformers, or within an aircraft or vehicle.
A 19-inch rack is a standardized frame or enclosure for mounting multiple electronic equipment modules. Each module has a front panel that is 19 inches (482.6 mm) wide. The 19 inch dimension includes the edges or ears that protrude from each side of the equipment, allowing the module to be fastened to the rack frame with screws or bolts. Common uses include computer servers, telecommunications equipment and networking hardware, audiovisual production gear, professional audio equipment, and scientific equipment.
A serial port is a serial communication interface through which information transfers in or out sequentially one bit at a time. This is in contrast to a parallel port, which communicates multiple bits simultaneously in parallel. Throughout most of the history of personal computers, data has been transferred through serial ports to devices such as modems, terminals, various peripherals, and directly between computers.
A hinge is a mechanical bearing that connects two solid objects, typically allowing only a limited angle of rotation between them. Two objects connected by an ideal hinge rotate relative to each other about a fixed axis of rotation, with all other translations or rotations prevented; thus a hinge has one degree of freedom. Hinges may be made of flexible material or moving components. In biology, many joints function as hinges, such as the elbow joint.
A deadbolt or deadlock is a type of lock morticed into a wooden door where a bolt is thrown into the door frame, using a key from either side, to secure the door. It is distinct from a spring bolt lock because a deadbolt can only be opened by a key or handle. The more common spring bolt lock uses a spring to hold the bolt in place, allowing retraction by applying force to the bolt itself. A deadbolt can therefore make a door more resistant to entry without the correct key, as well as make the door more resistant to forced entry. A deadbolt is often used to complement a spring-bolt lock on an entry door to a building.
A crash bar is a type of door opening mechanism which allows users to open a door by pushing a bar. While originally conceived as a way to prevent crowd crushing in an emergency, crash bars are now used as the primary door opening mechanism in many commercial buildings.
A utility pole, commonly referred to as a transmission pole, telephone pole, telecommunication pole, power pole, hydro pole, telegraph pole, or telegraph post, is a column or post, usually made out of wood or aluminum alloy, used to support overhead power lines and various other public utilities, such as electrical cable, fiber optic cable, and related equipment such as transformers and street lights while depending on its application. A Stobie pole is a multi-purpose pole made of two steel joists held apart by a slab of concrete in the middle, generally found in South Australia.
A door closer is a mechanical device that regulates the speed and action of a door’s swing. Manual closers store the force used to open the door in some type of spring and reuse it to close the door. Automatic types use electricity to regulate door swing behavior.
A bicycle lock is a security device used to deter bicycle theft, either by simply locking one of the wheels or by fastening the bicycle to a fixed object, e.g., a bike rack.
A fire door is a door with a fire-resistance rating used as part of a passive fire protection system to reduce the spread of fire and smoke between separate compartments of a structure and to enable safe egress from a building or structure or ship. In North American building codes, it, along with fire dampers, is often referred to as a closure, which can be derated compared against the fire separation that contains it, provided that this barrier is not a firewall or an occupancy separation. In Europe national standards for fire doors have been harmonised with the introduction of the new standard EN 16034, which refers to fire doors as fire-resisting door sets. Starting September 2016, a common CE marking procedure was available abolishing trade barriers within the European Union for these types of products. In the UK, it is Part B of the Building Regulations that sets out the minimum requirements for the fire protection that must be implemented in all dwellings this includes the use of fire doors. All fire doors must be installed with the appropriate fire resistant fittings, such as the frame and door hardware, for it to fully comply with any fire regulations.
A latch or catch is a type of mechanical fastener that joins two objects or surfaces while allowing for their regular separation. A latch typically engages another piece of hardware on the other mounting surface. Depending upon the type and design of the latch, this engaged bit of hardware may be known as a keeper or strike.
Manual fire alarm activation is the process of triggering a fire alarm through a call point, pull station, or other device. This usually causes the alarm to sound the evacuation signal for the relevant building or zone. Manual fire alarm activation requires human intervention, as distinct from automatic fire alarm activation such as that provided through the use of heat detectors and smoke detectors. It is, however, possible for call points/pull stations to be used in conjunction with automatic detection as part of the overall fire detection and alarm system. Systems in completed buildings tend to be wired in and include a control panel. Wireless activators are common during construction.
An electronic lock is a locking device which operates by means of electric current. Electric locks are sometimes stand-alone with an electronic control assembly mounted directly to the lock. Electric locks may be connected to an access control system, the advantages of which include: key control, where keys can be added and removed without re-keying the lock cylinder; fine access control, where time and place are factors; and transaction logging, where activity is recorded. Electronic locks can also be remotely monitored and controlled, both to lock and to unlock.
An electric strike is an access control device used for door frames. It replaces the fixed strike faceplate often used with a latch. Like a fixed strike plate, it normally presents a ramped or beveled surface to the locking latch allowing the door to close and latch just like a fixed strike would. However, an electric strike's ramped surface can, upon command, pivot out of the way when the lock on the door is in the locked position and the door is opened, allowing a user to pull/push the door to open it without operating the mechanical lock or using a mechanical key. After the door is opened past the keeper, the keeper returns to its standard position and re-locks when power is removed or applied, depending upon the strike's configuration.
A wildland fire engine or brush truck is a fire engine specifically designed to assist in fighting wildfires by transporting firefighters to the scene and providing them with access to the fire, along with water or other equipment. There are multiple types of wildfire apparatus which are used in different scenarios. According to the U.S. National Fire Protection Association, if the apparatus will be used primarily for outdoor and wildland responses, then it is to be considered a wildland fire apparatus and must conform to NFPA 1906.
An espagnolette is a locking device, normally mounted on the vertical frame of a French door or casement window. A handle or knob is connected to a metal rod mounted to the surface of the frame, about a metre above the floor. Operating the handle rotates the rod, which has hooks at each end that fit into sockets at the head and sill of the opening. This type of lock is often used on semi-trailer trucks to fasten the rear doors. It can be identified by the use of a round bar, instead of a half-round bar used on a crémone bolt.
Fire dampers are passive fire protection products used in heating, ventilation, and air conditioning (HVAC) ducts to prevent and isolate the spread of fire inside the ductwork through fire-resistance rated walls and floors. Fire/smoke dampers are similar to fire dampers in fire resistance rating, and also prevent the spread of smoke inside the ducts. When a rise in temperature occurs, the fire damper closes, usually activated by a thermal element which melts at temperatures higher than ambient but low enough to indicate the presence of a fire, allowing springs to close the damper blades. Fire dampers can also close following receipt of an electrical signal from a fire alarm system utilising detectors remote from the damper, indicating the sensing of heat or smoke in the building occupied spaces or in the HVAC duct system.
An electromagnetic lock, magnetic lock, or maglock is a locking device that consists of an electromagnet and an armature plate.
On February 27, 1975, fire broke out at the New York Telephone Company switching center at 204 Second Avenue and Thirteenth Street in the East Village of Manhattan, New York City. At this time, the building contained central offices for connecting local customer telephone lines, as well as toll switching systems. The fire disrupted service for 175,000 customers, connected within the building through 105,000 service loops. It was the worst single service disaster suffered by any single Bell operating company in the 20th century.