The NFPA 72 sets rules on minimum standards for protection in homes under Chapter 29. This includes smoke detector alarms & carbon monoxide warning equipment alarms.
Smoke Alarm Should Be Located on Each Level in Addition to Each Bedroom. In addition to smoke alarms outside of the sleeping areas and in each bedroom, Chapter 29 requires the installation of smoke alarm on each addtional level, including the basement.
Dedicated circuit for AC Smoke detectors Each detector is considered a station , each alarm stationmust have parallel power source available thru entire circuit , and must be interconnected. In the event one device has an alarm, all interconnedted devices must alarm "identical".
29.10.7.8.1 An open, ground fault, or short circuit of the wiring connecting input or output devices to the single or multiple station alarms shall not prevent operation of each individual alarm.
29.7.2 Carbon Monoxide Alarm Interconnection. Unless exempted by applicable law, codes, or standards, carbon monoxide alarms used to provide a warning function, and where two or more alarms are installed within a dwelling unit, suite of rooms, or similar area, shall be arranged so that the operation of any carbon monoxide alarm causes all carbon monoxide alarms within these locations to sound.
29.8.2.1.1 Interconnected Smoke and Heat Alarms. For other than mechanically powered single station heat alarms and uless exempted by applicable laws, codes, or standards, smoke or heat alarms used to provide a fire warning function, and where two or more alarms are installed within a dwelling unit, suite of rooms, or similar area, shall be arranged so that the operation of any smoke or heat alarm causes all alarms within these locations to sound.
29.10.7.6 Where common wiring is employed for a combination system, the equipment for other than the fire and carbon monoxide alarm system shall be connected to the common wiring of the system so that short circuits, open circuits, grounds, or anny fault in this equipment or interconnection between this equipment and the fire and carbon monoxide alarm system wiring does not interfere with the supervision of the fire and carbon monoxide alarm system or prevent alarm or trouble signal operation.
29.10.6.4 If a reset switch is provided, it shall be of self restoring (momentary operation) type.
29.10.9.8 Househould fire alarm systems shall be programmed by the manufacturer to generate at least a monthly test of the communication or transmission means.
Battery powered smoke alarms are not recommended. To be used at last resort.
29.11.1.4 (5) (b) Smoke alarms shall not remain in service longer than 10 years from the date of manufacture unless otherwise provided by manufacturer's published instructions.
29.11.2.1 The interconnection of alarms shall comply with the following. - (2) In no case shall more than 18 initiating devices be interconnected (of which 12 can be smoke alarms) where the interconnecting means is not supervised. - (3) In no case shall more than 64 initiating devices be interconnected (of which 42 can be smoke alarms) where the interconnecting means is supervised.
29.11.2.2 A single fault on the interconnecting means between multiple station alarms shall not prevent single station operation of any of the interconnected alarms.
29.11.3.4 Specific Location Requirements ---
(4) Smoke alarm and smoke detectors shall not be installed between 10 feet and 20 feet along a horizontal flow path from a stationary or fixed cooking appliance. Smoke detectors should be installed just over 20 feet from the stationary of fixed cooking appliance.
(6) Smoke alarms and smoke detectors shall not be installed within a 36 inch horizontal path from a door to a bathroom containing a shower or tub unless listed for installation in close proximity to such locations.
(7) Smoke alarms and smoke detectors shall not be installed within a 36 inch horizontal path from the supply registers of a forced air heating or cooling system and shall be installed outside of the direct airflow from those registers.
(8) Smoke alarms and smoke detectors shall not be installed within a 36 inch horizontal path from the tip of the blade of a ceiling suspended (paddle) fan unless the room configuration restricts meeting this requirement.
29.11.4.4 Heat detectors or alarms shall be mounted on the ceiling at least 4 inches from the wall or on the wall with the top of the detector or alarm not less than 4 inches nor more than 12 inches, below the ceiling.
A.29.11.4 While Chapter 29 does not require heat alarms or heat detectors as part of the basic protection scheme, it is recommended that the householder consider the use and placement of additional heat detectors. For example, additional heat alarms or heat detectors could be considered, but not limited to, the following areas: kitchen, dining room, attic (finished or unfinished), furnace room, utility room, basement, and integral or attched garage.
While Chapter 29 does not require total coverage in a home. Chapter 29 does recommend smoke, heat and carbon monoxide alarms for total coverage of the home. Total coverage shall include all rooms, halls, storage areas, basements, attics, lofts, spaces above suspended ceilings and other subdivisions and accessible spaces.
Common code violation in new custom homes is connecting all detectors to a single two wire daisy chained loop. The power to each smoke alarm is not parallel. In the event one smoke alarm is removed or serviced all other smoke detectors will fail to operate.