Editing Smoke detector (section)

== Commercial ==
[[File:Integrierte-feststellanlage.JPG|thumb|An integrated locking mechanism for commercial building doors. Inside an enclosure are a locking device, smoke detector and power supply.]]

Commercial smoke detectors are either conventional or addressable, and are connected to [[security alarm]] or [[fire alarm system]]s controlled by [[fire alarm control panel]]s (FACP).<ref name="ssspl">{{cite web|url=http://www.ssspl.org/uploads/Products/Pdf/firealarmsystem.pdf|title=Fire Alarm System|website=ssspl.org|access-date=8 May 2018|url-status=live|archive-url=https://web.archive.org/web/20170829094729/http://www.ssspl.org/uploads/Products/Pdf/firealarmsystem.pdf|archive-date=29 August 2017}}</ref> These are the most common type of detector and are usually significantly more expensive than single-station battery-operated residential smoke alarms.<ref name="ssspl" /> They are used in most commercial and industrial facilities and other places such as ships and trains,<ref name="ssspl" /> but are also part of some security alarm systems in homes.<ref>{{cite web|url=http://wiki.hometech.com/tiki-index.php?page=Adding+Smoke+Detectors+to+a+Security+System|title=Adding Smoke Detectors to a Security System|last1=Fisher|first1=Jeff|website=Wiki.hometech.com|publisher=TechWiki|access-date=6 June 2014|url-status=live|archive-url=https://web.archive.org/web/20140714145756/http://wiki.hometech.com/tiki-index.php?page=Adding+Smoke+Detectors+to+a+Security+System|archive-date=14 July 2014}}</ref> These detectors do not need to have built-in alarms, as alarm systems can be controlled by the connected FACP, which will set off relevant alarms, and can also implement complex functions such as a staged evacuation.<ref name="ssspl" />

=== Conventional ===
The word "conventional" is slang used to distinguish the method used to communicate with the control unit in newer addressable systems.<ref name="ssspl" /> So-called "conventional detectors" are smoke detectors used in older interconnected systems and resemble electrical switches by their way of working.<ref name="ssspl" /> These detectors are connected in parallel to the signaling path so that the current flow is monitored to indicate a closure of the circuit path by any connected detector when smoke or other similar environmental stimuli sufficiently influences any detector.<ref name="ssspl" /> The resulting increase in current flow (or a dead short) is interpreted and processed by the control unit as a confirmation of the presence of smoke and a fire alarm signal is generated.<ref name="ssspl" /> In a conventional system, smoke detectors are typically wired together in each zone and a single fire alarm control panel usually monitors several zones which can be arranged to correspond to different areas of a building.<ref name="ssspl" /> In the event of a fire, the control panel can identify which zone or zones contain the detector or detectors in alarm. However, they cannot identify which individual detector or detectors are in a state of alarm.<ref name="ssspl" />

=== Addressable ===
[[File:Truealarmdetector.JPG|thumb|right|An addressable Simplex TrueAlarm smoke detector]]
An addressable system gives each detector an individual number or address.<ref name="ssspl" /> Addressable systems allow the exact location of an alarm to be plotted on the FACP while allowing several detectors to be connected to the same zone.<ref name="ssspl" /> In certain systems, a graphical representation of the building is provided on the screen of the FACP which shows the locations of all of the detectors in the building,<ref name="ssspl" /> while in others the address and location of the detector or detectors in alarm are simply indicated.<ref name="ssspl" />

Addressable systems are usually more expensive than conventional non-addressable systems,<ref>{{cite web |title=Addressable Equipment |url=http://www.wi-ltd.com/fire/Fire_Detection_Systems/Addressable_Systems/Addressable_Equipment |url-status=live |archive-url=https://web.archive.org/web/20091124071304/http://www.wi-ltd.com/fire/Fire_Detection_Systems/Addressable_Systems/Addressable_Equipment |archive-date=2009-11-24 |access-date=2010-06-09 |publisher=Westminster International Limited}}</ref> and offer extra options, including a custom level of sensitivity (sometimes called Day/Night mode) which can determine the amount of smoke in a given area and contamination detection from the FACP that allows determination of a wide range of faults in detection capabilities of smoke detectors.<ref name="ssspl" /> Detectors become contaminated usually as a result of the build-up of atmospheric particulates in the detectors being circulated by the heating and air-conditioning systems in buildings. Other causes include carpentry, sanding, painting, and smoke in the event of a fire.<ref>{{cite web|url=http://firewize.com/contaminated-smoke-detectors|title=Contaminated (dirty) Smoke Detectors|date=2012|website=Firewize.com|publisher=Firewize Holdings Pty|access-date=6 June 2014|url-status=live|archive-url=https://web.archive.org/web/20140729162623/http://firewize.com/contaminated-smoke-detectors|archive-date=29 July 2014}}</ref> Panels can also be interconnected to monitor a large number of detectors in multiple buildings.<ref name="ssspl" /> This is most commonly used in hospitals, universities, resorts and other large centres or institutions.<ref name="ssspl" />