At first glance, you’d be tempted to simply position the smoke detector on a shelf and not bothering installing it on the wall or ceiling, but since you want it to detect the smoke as fast as possible, you should mount it on the ceiling and a bit further from the corners of the room it’s also ideal to keep it at least 15 feet away from a fuel burning heat source, so it won’t trigger those annoying false alarms. That being said, the installation process is simple and intuitive: all you have to do is remove the card from the bottom of the mounting bracket, attach the ring to the ceiling or wall using the fixing anchors they’re provided inside the package, fortunately and afterwards, simply rotate the alarm into place. The most popular types of sensors that are used to detect the smoke particles are the ionization sensors and the photoelectric sensors some manufacturers have developed their own proprietary sensors to detect more than one type of fires, such as the case of the Nest Protect with its Split Spectrum sensor. The ionization sensors are used to detect the small particles from fast burning fires, but because of their nature, they’re more prone to false alarms these type of sensors are usually found built into older smoke detectors. The photoelectric sensors can detect larger particles, so it is a lot more useful for smouldering fires those which have not yet erupted into flames, so they’re better for an early detection and are less likely to trigger false alarms. The First Alert P1010 uses the aforementioned technology, so it has a beam of light inside a small chamber which does not directly hit the photoelectric sensor, but, the moment smoke particles enter the device through the holes in the metallic section, the light gets diverted and it will immediately hit the sensor, thus sounding the alarm.