This document specifies general requirements for the construction, testing and performance of electrically operated carbon monoxide gas detection apparatus, designed for continuous operation in a fixed installation in recreational vehicles and similar premises including recreational craft. NOTE For caravan holiday homes EN 50291-1 applies. This European Standard specifies apparatus designed to operate in the event of an escape of carbon monoxide and to provide a visual and audible alarms only (Type B of EN 50291-1), or to provide visual and audible alarms and an executive action in the form of an output signal that can actuate directly or indirectly a shut-off device and/or other ancillary device (Type A of EN 50291-1). This European Standard excludes apparatus for the detection of combustible gases, other than carbon monoxide itself (see EN 50194-1), for the detection of CO in industrial installations (see EN 45544-1, EN 45544-2 and EN 45544-3) or commercial premises, for CO measurement for smoke and fire detection.