Editing Kill switch (section)

{{short description|Safety mechanism to quickly shut down a system}}
{{use American English|date=January 2023}}
{{use mdy dates|date=January 2023}}
{{about|the safety mechanism|other uses|Kill switch (disambiguation)}}
{{redirect|Emergency stop|when trains make an emergency stop|Emergency brake (train)}}
{{Infobox machine
| name           = Kill switch
| image          = Not-Aus Betätiger.jpg
| caption        = A kill switch without a cover
| classification = Mechanical component
| industry       = Automotive, boating, energy, engineering, entertainment
| application    =
| dimensions     =
| weight         =
| fuel_source    =
| powered        = Varies, some mechanical
| self-propelled =
| wheels         =
| tracks         =
| legs           =
| aerofoils      =
| axles          =
| components     =
| invented       =
| inventor       =
| examples       =
}}
A '''kill switch''', also known more formally as an '''emergency brake''', '''emergency stop''' ('''E-stop'''), '''emergency off''' ('''EMO'''), or '''emergency power off''' ('''EPO'''), is a [[safety]] mechanism used to shut off [[Machine|machinery]] in an [[emergency]], when it cannot be shut down in the usual manner.  Unlike a normal shut-down [[switch]] or shut-down procedure, which shuts down all systems in order and turns off the machine without damage, a kill switch is designed and configured to abort the operation as quickly as possible (even if it damages the equipment) and to be operated simply and quickly (so that even a [[panic]]ked operator with impaired [[executive functions]] or a bystander can activate it). Kill switches are usually designed to be noticeable, even to an untrained operator or a bystander.

Some kill switches feature a removable, protective barrier against accidental activation (e.g. a [[plastic]] cover that must be lifted or [[glass]] that must be broken), known as a[[wiktionary:molly-guard| mollyguard]]. Kill switches are features of mechanisms whose normal operation or foreseeable misuse might cause [[injury]] or [[death]]; industrial designers include kill switches because damage to or the destruction of the machinery is less important than preventing workplace injuries and deaths.

A similar system, usually called a [[dead man's switch]], is a device intended to stop a machine (or activate one) if the human operator becomes incapacitated or leaves the machine unattended, and is a form of [[fail-safe]]. They are commonly used in industrial applications (e.g., [[locomotive]]s, [[tower cranes]], [[freight elevator]]s) and consumer applications (e.g., [[lawn mower]]s, [[Tractor|tractors]], [[personal watercraft]], [[Outboard motor|outboard motors]], [[snow blower]]s, [[motorcycle]]s and [[snowmobile]]s). The switch in these cases is held by the user, and turns off the machine if they let go. Some riding lawnmowers have a kill switch in the seat which stops the engine and blade if the operator's weight is no longer on the seat.