Smoke alarms, or at least ionization-based alarms with a tiny amount of radioactive americium, are very simple devices. Inside the alarm, there’s a metal can – an ionization chamber – with ...

The light beam stays fixed, pointed across the inside of a chamber inside the device. When smoke particles disrupt the light beam, the sensor sets off the alarm. Smoldering fires can be caused by ...

In fact we all probably have just such a device in our houses, in the form of the ionisation chamber that’s part of most household smoke detectors. [Lukas Koch] has built a project that shows us ...

Smoke and carbon monoxide detectors have a simple but critical purpose. They have to quickly detect those two life-threatening components that might quietly fill the air so that you can get to safety.