Wireless Connected Smoke Detectors:
Nine Models Reviewed

Published November 2011
Revised December 2011
Authored by Bryce Nesbitt, Reviewpress Editor

Introduction
If a smoky fire started in your garage, would you want an alarm to sound upstairs in your bedroom? Most people would, yet the smoke detectors commonly stocked in hardware and home stores can't do that.

This review covers wireless connected smoke detectors, which can be used alone or in combination with existing alarms. This guide covers all the available options, and helps you to find a retailer who can supply the units.

Why should I consider such units?

Fire escape times are very short: the more notice you have the better. A 2005 study pegged escape time in a modern home at three minutes (1). After that time a fire is likely to “flash over” rendering the house lethal. Quicker notice can save lives and reduce property damage. A fire could smoulder for hours in part of the house, yet if you don't hear the alarm you can't react.

How do these units work?
These alarms work by sending radio signals. Generally you set all alarms in your home to a common code. To test, press a button on one alarm, and verify that all the alarms beep together. The process is fairly easy.

The models from Kidde work much like older garage door openers. You flip each unit over and set a code. All units with the same code operate together. A green flashing light identifies the unit that started the alarm.

The OneLink models from First Alert must be "paired", a somewhat more involved process. You place two units next to each other and make a series of button presses. Although nothing visible has changed, the units will now operate together.

With OneLink voice models the room name is announced (e.g. “Evacuate! Fire detected in basement. Evacuate!”). On non-voice units a light indicates the source of the alarm.

Are There Any Downsides?

The wireless models run through batteries considerably quicker than the best conventional smoke alarms. We calculated about a one year lifespan, based on laboratory tests.

Connected units can make false alarms considerably more annoying: and that can be a big problem. More than half (54%) of smoke alarm failures in real fires were caused by missing batteries ³. Nuisance alarms are a major cause of battery removal.

If you're willing to take on the extra burden of battery replacement, connected alarms are worth a look. If you have problems with false alarms, solve that problem first.

What do I need for my home?

The following feature grid can help you find a model for your particular situation.

If your alarms must wake children or elderly persons, consider a talking model. Old people may have hearing loss making it impossible to hear a high pitched horn. Studies suggest that children are more likely to wake to a voice alarm. First Alert makes a model (the ONELINK-C2) specifically marketed as more likely to wake a child.

As of 2011, over half the US states mandate carbon monoxide detector installation even in existing homes. This may be your opportunity to add CO detection.

Ionization or Photoelectric?

Ionization type detectors are better at detecting fast moving fires. Photoelectric detectors are better for slow smoldering fires. Ideally you'd have both. Except in this category you can't: neither company makes both types. You can't do much about this other than to retain at least one non-connected alarm of the opposite type.

If you have problems with false alarms, read up elsewhere on this topic. Switching detector types may solve your problem and save your ears.

Some dual sensor types exist which claim to be highly resistant to false alarms. As of this writing they are not available in a wireless connected model.

Wisdom of the crowd
We've asked owners of these products to report back their experiences:

Review Section 2: The Details

Why are smoke alarms important?

You have only three minutes to escape from an average home fire, according to a 2005 study by the National Institute of Standards and Technology.

In one-quarter of reported fires in smoke alarm-equipped homes, the devices did not work. If all homes had working smoke alarms, an estimated 890 lives could be saved annually, or just under one-third the annual fire death toll ².


Other Characteristics to Consider
Smoke testing of these models is out of the scope of our review. However, all the models meet applicable standards. Good smoke testing reviews have appeared in Australia-based Choice magazine, and New Zealand's Consumer magazine.

Larger homes our outbuildings may present barriers to wireless signals. The OneLink models are superior in this regard, as the signal can "hop" from detector to detector until it reaches all units.

Problems and Annoyances
Numerous OneLink alarms manufactured before March 3rd 2006 were recalled, due to a defect causing short battery life. Call First Alert customer service for details on replacement options.

OneLink alarms can become "unpaired". If a battery dies and is not replaced quickly the unit can return to factory settings. For this reason it is important to periodically test the alarms and actually verify each one sounds. Note this can be tricky... with 4-5 alarms blaring in a single house it can be devilishly hard to determine where the sound is coming from.

Some users have reported interference problems, particularly with Kidde models and wireless security systems operating on the same frequency. For this reasons we recommend using smoke alarms matched with your wireless security system. Note that problems can even occur with your neighbor's security system: wireless signals don't respect property boundaries. The 915 Mhz radio band is "unlicensed", meaning anybody can make products that operate in this band, and dozens of products now exist. The OneLink models use a frequency hopping technique that should result in good performance even in areas with lots of interference.


ReviewPress Speaks: What we'd like to see in this category

We'd like to see easier testing. Pressing a test button while on a stepladder is hard enough without a 85 decibel horn blaring in your ear. None of the above models is easy to test.

It can be difficult to determine if all units are working, particularly with the OneLink models. We'd like to see units that give a full talking status report at a reasonable (not ear splitting) volume. An example test button might speak: "Four units reported OK status. Unit three has battery at 66%. Unit four has poor reception and should be moved".

These units should be smart enough to detect a missing alarm. If you “paired” four alarms, and a year later only three respond, that should be noted when you test the alarms.

Kidde's own documentation reads "Kidde strongly recommends that both ionization and photoelectric smoke alarms be installed to help insure maximum detection of the various types of fire that can occur within the home.". Yet Kidde does not offer a photoelectric option. Similarly BRK Brands does not offer photoelectric or combination OneLink models. This is inexcusable on the part of both companies, and should be remedied.

Keywords
interconnected, hard-wire, wireless, smoke alarm, home safety, fire, alarm, ANSI/UL 217, ANSI/UL 2034, NFPA 72

¹ Ahrens, M, April 2008, U.S. Experience with Smoke Alarms and Other Fire Detection/Alarm Equipment, National Fire Protection Association, Quincy, MA