A smoke detector is a device that is used to detect smoke. There are basically two types of smoke detector systems, one that has smoke detector wiring that issues a signal to a monitored fire alarm system and the other, known as smoke alarms, generally issue a local audible and/or visual alarm from the detector itself.
In the State of Michigan the required number and placement of smoke detectors is based upon standards established in the National Fire Prevention Association (NFPA 72) fire code. Laws governing the installation of smoke detectors vary from jurisdiction to jurisdiction. The state of Michigan requires smoke detectors on every habitable level and in attics that are accessible, and within the vicinity of all bedrooms.
In new construction, minimum requirements are typically more stringent. All smoke detector wiring must be hooked directly to the electrical wiring system, be interconnected and have a battery backup. Some jurisdictions also require smoke detectors in stairways, main hallways and garages.
Wired units allow a dozen or more detectors to be connected, so that if one detects smoke, the alarms will sound on all the detectors in the network, improving the chances that occupants will be alerted, even if they are behind closed doors or if the alarm is triggered one or two floors removed from their location. Smoke detector wiring with interconnections may only be practical for use in new construction, especially if the wire needs to be routed in areas that are inaccessible without cutting open walls and ceilings.
Most residential smoke detectors run on 9-volt alkaline or carbon-zinc batteries. When these batteries run down, the smoke detector becomes inactive. When the battery is low, most smoke detectors will signal with a chirping sound at regular intervals.
Most modern smoke alarms come with a lithium battery that can run for about 7 to 10 years. These items traditionally are replaced in full when the battery life runs out.
Current Electrical Systems have a full range of smoke detectors and are happy to provide advise on the benefits of battery operated alarms through to hard wired alarms.
Depending on where you live, your project may be eligible for a free extended warranty through IBEW Local 252. Learn more »