These requirements cover electrically operated single- and multiple-station carbon monoxide (CO) detectors intended for protection in ordinary indoor locations of family living units, including recreational vehicles and mobile homes. For the purpose of these requirements, a family living unit means a housekeeping unit, used or intended to be used as a domicile by one or more persons and usually containing cooking, eating, living, sleeping and sanitary facilities.
Carbon monoxide detectors covered by these requirements are intended to respond to the presence of carbon monoxide from sources such as, but not limited to, exhaust from internal-combustion engines, abnormal operation of fuel-fired appliances, and fireplaces. Carbon monoxide detectors are intended to detect carbon monoxide levels below those that could cause a loss of ability to react to the dangers of carbon monoxide exposure.
These requirements, where applicable, also cover all remote accessories that may be connected to or are intended to be employed with a single- or multiple-station carbon monoxide detector. See Clause 30.3.
This standard does not cover the following:
(a) Single- and multiple-station smoke detectors or smoke alarms that are covered by UL 217 or ULC-S531.
(b) Smoke detectors of the non-self-contained type that are intended for connection to a household or industrial system control unit. These are included in the Standard for Smoke Detectors for Fire Protective Signalling Systems, UL 268 or ULC-S529;
(c) Mechanically operated single- and multiple-station fire alarm devices that are specified in the requirements for single- and multiple-station heat detectors, UL 539 or ULC-S530;
(d) Heat detectors whose requirements are covered in the Standard for Heat Detectors for Fire Protective Signalling Systems, UL 521 or ULC-S530.
A product that contains features, characteristics, components, materials, or systems new or different from those in use when the standard was developed, and that involves a risk of fire, electric shock, or injury to persons shall be evaluated using the appropriate additional component and end-product requirements as determined necessary to maintain the level of safety for the user of the product as originally anticipated by the intent of this standard.