What home, cottage, and commercial buyers need to know about: Smoke detectors

In our home, cottage and commercial inspections throughout Orillia, Gravenhurst, Bracebridge, and Muskoka we often find missing smoke detectors, old smoke detectors, smoke detectors that have the batteries removed, and wired in detectors with the breaker shut off.  When we do  find issues like this we write this up as a defect in our inspection reports. Here is what home, cottage , and commercial buyers need to know about smoke detectors
A smoke detector is an electronic device that detects smoke in the air, assumes it is the result of fire and gives an audible warning. There are two types of detector: photoelectric and ionization, both come in battery operated or wired in models. Each type may have additional features such as:  a missing battery indicator, an alarm hush or silence feature,  a power "on" indicator light,  dual sensor units and combination hardwired/battery backup units.

Photoelectric?  Ionization? what does that mean and how do they work.

A photoelectric type smoke alarm consists of a light emitting diode and  a light  sensitive sensor in the sensing chamber. The presence of suspended products of combustion in the chamber scatters the light beam. This scattered light is detected and sets off the alarm.

An ionization smoke alarm uses a small amount of radioactive material to ionize air in the sensing chamber. As a result, the air chamber becomes conductive permitting current to flow between two charged electrodes. When products of combustion enter the chamber, the conductivity of the chamber air decreases. When this reduction in conductivity is reduced to a predetermined level, the alarm is set off. Most of the smoke alarms presently in use are ionization type detectors.

Is one type better than the other?

The fire protection and prevention industry recognizes  that neither sensor type, photoelectric or ionization, is universally better at detecting all types of fires.  Each of the sensors operate on a different principle and will respond differently to various conditions. In general Ionization sensors may respond slightly faster to flaming fires, where the photoelectric sensors may respond slightly faster to smouldering fires.
Photoelectric models are best suited for living rooms, bedrooms and kitchens because these rooms usually have large pieces of furniture: sofas, mattresses, cabinetry, etc. which will burn slowly and create more smoke than flames.

Ionization models are best used for rooms that contain highly combustible materials that can create flaming fires. These types of materials include flammable liquids like the oil in a fry pan, newspapers,  paint cleaning solutions, etc. Keep in mind, both alarms must be tested to the same ULC listing standard. The alarms must meet the same requirements.

Where should smoke alarms be installed?

At the minimum smoke alarms should be installed on every level and outside all sleeping areas. Note though that the Office of the Fire Marshal also recommends that smoke alarms be installed in every room for maximum protection. A mix of photoelectric and ionization smoke alarms is best. Smoke detectors should be installed a minimum of three feet away from air-conditioning and heating registers, and be located less than twelve inches below the highest point of the ceiling in the room it serves.

Smoke detectors must be installed consistent with the Building Codes in affect at the time of original construction. Additional detectors should be installed to bring protection to code when additions or alterations to the structure are undertaken.  All homes, cottages, and commercial units are required to have at least one working smoke detector.  Unless prohibited by local rules, regulations, or ordinances, a battery-operated smoke detector will be deemed to satisfy the requirements. For our clients in 0rillia, Gravenhurst, Bracebridge, and Muskoka, we categorically recommend that all sleeping rooms be equipped with functional smoke detectors, regardless of the minimum standards.

Nuisance alarms

I am sure that everyone has by now heard dad holler when the fire alarm goes off '  dinner's ready", as amusing  as that is, except to the cook of course, nuisance alarms are a fairly common thing, and it seems to be the kitchen alarm that goes off the most often. We recommend  our clients install a photoelectric smoke alarm in the kitchen area to minimize nuisance alarms. . Fire safety websites often state that photoelectric smoke alarms, when installed in the kitchen area, are less prone to nuisance alarms than the ionization type alarm and that has been our experience too. While you could just relocate the current alarm, that will pose problems if it is a wired in model

Our focus is on client safety and peace of mind

We stress to our clients during the inspection the most important factor in protecting your family, guests, or customers, is having the recommended number of working smoke alarms installed in the proper locations. For safety we also recommended that since clients can not be sure what type of fire might start in your home, cottage or commercial building, they should install both ionization and photoelectric alarms or install dual sensor smoke alarms which feature both sensors in one unit. We will recommend replacing all smoke detectors if  they are older units 7 + years.  Currently, all manufacturers recommend their smoke alarms be replaced at ten years of age.  As the detector elements age they become less and less reliable.

Clients looking to buy properties with older smoke alarms are advised to start with new units throughout the property that way the replacement date is known and can be written inside the cover when installed.  During our home, cottage, and commercial inspections in Orillia, Gravenhurst, Bracebridge, and Muskoka, we do not operate smoke detectors, pushing the test button only tests that the buzzer is functioning, nor do we smoke-test detectors, doing so is often objectionable to property owners but is the only definitive test to confirm proper function.