Reliable and very responsive

I installed the smoke detector in September 2013 at a place away from drafts in a space leading to the upper floor of a dwelling house. His alarm went off for the 1st time recently, in early December 2014, when I had to light a fire in my wood stove and a little smoke comes escaped due to poor draft due to the wind. I can only attest to the effectiveness and responsiveness of the sensor that is triggered within 20 to 30 seconds when it was located 5 m from where this very low smoke emission was occurred.