Oregon has several sets of rules for smoke alarms. Some rules apply to newly constructed houses, some apply to renovated houses, and some apply to rentals, but the rules that I’ll write about today have to with houses that are being sold.
(Note: If you’re interested in the very important and surprising differences between ionization and photoelectric smoke alarms, read our blog about that subject. The following blog focuses on the more general rules about smoke alarms.)
Old Alarms are No Good
Smoke alarms wear out and eventually stop being reliable:
- All smoke alarms are only good for 10 years. This is a manufacturer’s rule and every manufacturer is the same in this regard. You can find the manufacture date on the back of the alarm. Sometimes it’s encoded, sometimes it’s difficult to read, sometimes it’s hidden behind the battery, and, occasionally, with really old alarms, it’s not there at all. If you can’t find the date, it’s a pretty good bet that the alarm is more than 20 years old. When an alarm is more than 9 or 10 years old, or if you’re in doubt about its age, just replace it.
Rule #1: Smoke alarms have to be less than 10 years old.
Provide Proper Power
Smoke alarms come with two kinds of power sources: solely battery powered and hardwired. You can’t use the solely battery powered ones in many cases.
- In the mid-1970s, when Oregon first started to require smoke alarms in houses, battery-powered alarms were rare, so most of the smoke alarms were hardwired. By the early ‘80s, battery-powered smoke alarms were common and the code adapted to avoid them. Starting in 1983 and ever since then, all smoke alarms in new construction (or in significantly remodeled homes) have been required to be hardwired. If a house ever had hardwired alarms, then you have to always have hardwired alarms in those locations.
- People often buy solely battery-powered alarms and install them right over the hardwired smoke alarm outlets. This is wrong: first, battery-powered alarms are less reliable, and second, they’re not listed to be installed over 120-volt wiring boxes, so don’t do that.
- If the house never had any hardwired smoke alarms, it’s fine to use the solely battery-powered kind, but if they use ionization sensors, be sure to use 10-year lithium batteries.
- Starting in 1993, all of the smoke alarms in new houses were required to be interconnected, so that if one sounded, they all sounded.
Rule #2: Once hardwired, always hardwired. Use battery-powered alarms only when the house lacks provisions for hardwired ones. (Of course, all hardwired alarms should have backup batteries.) Wherever it’s present, use interconnect wiring to ensure that when one alarm sounds, they all sound.
Put Them in the Right Places
Oregon has two basic rules for locating smoke alarms:
- For a start, Oregon requires houses to have one smoke alarm on each level (including basements, but excluding crawlspaces and non-habitable attics). They should be placed outside the bedrooms and, when on a 2nd floor, above the stairway.
- In addition, Oregon also requires smoke alarms in any location where they were required when the house was built. Since they started to be required in each bedroom in 1996 that means all post ’96 houses should have smoke alarms on each level, above the stairway, and in each bedroom.
Rule #3: Every house should have one smoke alarm on each level, near the bedrooms and above the stairway. In addition, one is required at every location where one was required when the house was built.
Don’t Put Them in the Wrong Places
Here are a few of the places where you shouldn’t put smoke alarm:
- Smoke alarms should be placed on ceilings or on walls within 12” of ceilings, but in no case should they be installed within 4” of the corner between a wall and a ceiling. That’s a dead-air space; smoke might not circulate there.
- Never place an ionization smoke alarm within 36” of a bathroom that contains a tub or shower; steam can cause nuisance alarms. (This can make it tricky to place smoke alarms near bedroom doors in smaller houses.)
- Keep all smoke alarms at least 36” away from paddle fan blades.
- Ensure that smoke alarms are not placed in the air stream from a heating or cooling supply register.
- Don’t put smoke alarms in kitchens. They provide too many opportunities for nuisance alarms.
- Don’t put smoke alarms in garages, unfinished attics, unheated storage spaces, or any other location where the temperature can drop below 40°F. Smoke alarms won’t work properly at low ambient temperatures.
Rule #4: Don’t put smoke alarms in places where the smoke can’t reach them, where steam and cooking fumes can reach them, or in places where it can get very cold.
Detectors and Alarms are Different
People often exchange the two terms, but smoke “alarms” and smoke “detectors” are different things:
- A smoke “alarm” is a self-contained unit: one box senses the smoke and sounds the alarm.
- A smoke “detector” doesn’t do that. It only senses the smoke and sends the information to another box – usually a central alarm panel – that, in turn, sounds an alarm and might also alert the fire department.
- Smoke detectors (part of a larger central alarm system) don’t comply with Oregon’s rules for smoke alarms unless they’re set up so that they work regardless of whether or not they’re being monitored by an alarm company and if the occupant has the ability to “hush” the alarm from the control panel.
Rule #5: If you have a central alarm system, make sure that the system will produce an alarm even when it’s not monitored and be sure that the alarm can be hushed at the control panel. Otherwise, install independent smoke “alarms” that are separate from the central alarm system.