At the moment, my smoke alarm has a heat sensor and so goes off when it thinks there is an excessive temperature rise. This is good in some ways because when I burn food it won’t go off from the smoke, however it does go off when I make toast. Alternatively, smoke detectors will go off when food is burnt, even though there might not be a fire. Another problem with fire alarms is that they need to be tested and batteries need to be replaced.
The Nest smoke alarm is the smartest smoke alarm that I have seen so far. It alerts the occupants in the house and people who have their phone connected to the alarm if there is smoke or carbon monoxide and where it is coming from. It does this with a voice first, so if it is not actually a fire then the alarm can be silenced on a phone before it begins to sound. It can also connect to the Nest thermostat and turn off gas supplies when it detects smoke, in addition to also being able to connect to some cookers and turn them off as well.
I think it is a very good product and solution, especially when compared to the smoke alarms fitted in most people’s homes. However it still requires user interaction if it thinks there is a fire, and is not able to determine by itself if there actually is.
I think that multiple sensors can be combined to determine if there actually is a fire. Combining smoke and heat sensors will already be more accurate than just one or the other, however also using infrared sensors to detect the amount of infrared rays should make it a lot easier for the alarm to determine if there is actually a fire.
Having a carbon monoxide sensor in the alarm is essential in my opinion, and the alarm should use a different sound or flash a different coloured light to show this. This is because humans are not able to detect carbon monoxide, and so rely solely on the alarm to warn us.
If the alarm is connected to wifi then it can also connect to other home appliances such as smart lights, and turn them on when there is a fire to help the occupants with their escape.
In terms of not having to test and replace the alarm’s batteries, the simplest method would be to have a wired fire alarm that connects to a power supply. Alternatively, there is an emerging technology where wireless charging can be carried out within a couple of metres of the power source. If this technology becomes more readily available then it could be used to keep the alarm powered.
There can also be many other things that can be built into an alarm such as a sprinkler or camera that can show the user on their phone what the situation is. However the more features that are added, the more expensive it will cost. The Nest alarm costs £99 and contains only a smoke and carbon monoxide detector; although it does also contain more chips for it to communicate via wifi and to do some data processing. Considering smoke alarms can be claimed for free from the fire brigade, paying £99 would be considered as unnecessary by many.
As always, if you think you have a solution or if you have a problem you would like me to try to solve then please feel free to comment it.