These requirements cover toxic and combustible gas and vapor detectors and sensors intended to be portable or employed in indoor or outdoor locations in accordance with the National Electrical Code@ NFPA 70. A gas detector and/or sensor and/or vapor detector@ as covered by these requirements@ consists of an assembly of electrical components coupled with a sensing means inside a chamber@ or by separate components to detect toxic and/or combustible gases or vapors. The detector includes provision for the connection to a source of power and signaling circuits.These requirements cover the following types of detectors: a) Detectors intended for monitoring the environment and detectors intended for open area protection and for connection to a compatible power supply or control unit for operation as part of gas detection or emergency signaling systems; b) Detectors intended solely for control of ventilation or shut off devices such as fans or control valves; c) Detectors intended for both the above applications; d) Sensors and sensing circuits intended for use with or in gas detectors@ alarms or gas detection circuits within fuel cell systems; e) Portable gas detectors; f) Multi-gas gas detectors; g) Multi-gas sensors and h) Equipment intended for use in hazardous locations. Note@ the equipment must comply with the applicable hazardous location requirements prior to evaluation to UL 2075.These requirements also cover all remote accessories that are intended to be connected to a gas or vapor detector and/or sensor.This standard does not cover the following: a) Control units to which the detectors are intended to be connected that are covered by the Standard for Control Units for Fire-Protective Signaling Systems@ UL 864; b) Control units to which the detectors are intended to be connected that are covered by the Standard for General Purpose Signaling Devices and Systems@ UL 2017; c) Self-contained single and multiple station carbon monoxide alarms or residential combustible gas detectors@ not intended for connection to a system control unit@ that are covered by the Standard for Single and Multiple Station Carbon Monoxide Alarms@ UL 2034 or Residential Gas Detectors@ UL 1484.Users of these requirements will additionally need to ensure that influencing factors not addressed in this standard for the end product installation@ such as mechanical movement@ field placement of conductive material@ and product damage@ will not affect the system for insulation coordination or performance operation. Examples are the deformation of the enclosure@ movement of the fittings for conduit or armored cable@ or the improper installation of field wiring.?