View source for Tripwire

{{Short description|Passive triggering mechanism}}
{{other uses}}
{{Use dmy dates|date=April 2024}}
[[File:Trip-wire pipe bomb.jpg|thumb|Simulated tripwire [[pipe bomb]]]]
{{Wiktionary}}
A '''tripwire''' is a passive [[:wikt:trigger|trigger]]ing mechanism.  Typically, a wire or cord is attached to a device for detecting or reacting to physical movement.

== Military applications ==

Such tripwires may be attached to one or more [[Land mine|mines]]⁠{{nowrap|{{tsp}}{{mdash}}{{tsp}}}}especially fragmentation or [[bounding mine]]s⁠{{nowrap|{{tsp}}{{mdash}}{{tsp}}}}in order to increase the area where triggering may occur. Trip wires are frequently used in [[booby trap]]s⁠{{nowrap|{{tsp}}{{mdash}}{{tsp}}}}where either a tug on the wire, or the release of tension on it, will trigger the explosives.

Soldiers sometimes detect the presence of tripwires by spraying the area with [[Silly String]]. It will settle to the ground in areas where there are no wires; where wires are present, the "strings" will rest on the taut wires without triggering the explosive, due to the product's light weight. Its use in detecting tripwires was first discovered in 1993 by Sergeant First Class David B. Chandler, Chief Instructor of the [[United States Army]]'s [[Sapper Leader Course]]. That year it was introduced to students attending the course, and it was later used in combat for this purpose by U.S. troops in the [[Iraq War]].<ref>{{cite magazine | url=http://www.time.com/time/magazine/article/0,9171,1561143,00.html | archive-url=https://web.archive.org/web/20061206005437/http://www.time.com/time/magazine/article/0,9171,1561143,00.html | url-status=dead | archive-date=6 December 2006 | title=Not So Silly String in Iraq | magazine=Time | accessdate=16 October 2007 | date=19 November 2006 | first=Ellin | last=Martens}}</ref><ref name="CBS News 16 October">{{cite news | url=https://www.cbsnews.com/news/a-serious-use-for-silly-string/ | title=A Serious Use For Silly String | publisher=CBS News | accessdate=16 October 2007 | date=6 December 2006| archive-url=https://web.archive.org/web/20201028130058/https://www.cbsnews.com/news/a-serious-use-for-silly-string/ | archive-date=28 October 2020 }}</ref><ref name="The Raw Story 16 October">{{cite news | url=http://www.rawstory.com/news/2006/FOX_VIDEO_Silly_String_saving_lives_1204.html | title=FOX VIDEO: 'Silly String' is saving lives over in Iraq | publisher=The Raw Story | accessdate=16 October 2007 |archiveurl = https://web.archive.org/web/20071012184140/http://rawstory.com/news/2006/FOX_VIDEO_Silly_String_saving_lives_1204.html <!-- Bot retrieved archive --> |archivedate = 12 October 2007}}</ref>

Another detection method is the use of green [[line laser]]s to illuminate and thus expose trip and command wires.  The bright laser beam reflects off the tripwire and can be seen by the user.

== Industrial applications ==

A tripwire may be installed in the vicinity of industrial equipment, such as a [[conveyor belt]] to enable workers to stop the equipment quickly.<ref>{{cite web
| url = http://m.eaton.com/ecm/idcplg%3FIdcService%3DGET_FILE%26allowInterrupt%3D1%26RevisionSelectionMethod%3DLatestReleased%26noSaveAs%3D0%26Rendition%3DPrimary%26dDocName%3DPCT_471543
| title = Safe and reliable conveyor belt stopping, where and whenever it is needed
| quote = The conveyor trip switch, is a safety switch that has a pretension device which allows the trip wire to be tensioned.
| publisher = Eaton}}</ref> These may also be called [[emergency stop]] pull-cords.<ref>{{cite web
| url = https://machinerysafety101.com/2018/08/28/emergency-stop-pull-cords/
| title = Machine Safety 101
| date = 28 August 2018
| publisher = Compliance InSight Consulting Inc.}}</ref>

== References ==
{{Reflist}}

[[Category:Anti-personnel weapons]]
[[Category:Warning systems]]
[[Category:Security]]