Where abouts should a carbon monoxide detector be placed ?? 

Hi

At room temperature carbon monoxide (CO) has about the same density as air, so the height of the sensor is not that crucial, as the gas spreads evenly in the room. However, it makes sense to install the CO alarm at a height where you can easily see the display or LED lights. This allows you to monitor the device better and to replace batteries easily (where that is required). Also, you need to stay away from areas with fresh air draughts (windows, doors) and spikes in CO creation due to the lighting of a fire or boiler (eg don't install the alarm in a boiler cabinet).

Harry