Abstract: An air purifier is presented with a sensor controlling a motorized fan, wherein the sensor continuously and automatically adjusts the sensitivity setting of the sensor as the quality of air being purified changes. The average air quality readings of the air passing through an air purifier are monitored over a designated time period and, as the quality fluctuates, the sensitivity of the sensor is automatically adjusted. If the air quality is poor (i.e. a high particulate count), the sensitivity of the sensor will be adjusted to a less sensitive setting (i.e. allowing higher fan speeds so that more air can be moved through the filter) and, if the air quality is good (i.e. a low particulate count), the sensitivity of the sensor will be adjusted to a more sensitive setting (i.e. setting a lower maximum fan speed because not as much air needs to move through the filter).

Abstract: A control system in an air monitor is programmed to selectively direct air from more than one source over a sensor and various algorithms are then used to provide feedback regarding the difference between the particulate readings at each of the sources. In one embodiment, a data curve for a reading from one air source during a first time period is overlaid with a line which is linearly extrapolated beyond the end of that time period and the data curve for a reading from a second air source during an immediately subsequent second time period is overlaid with a line which is linearly extrapolated beyond the start of that time period. The difference in the contaminant level between the extrapolated lines at the end of the first time period and the beginning of the second time period approximates the difference in contaminant content between the two air sources.

Abstract: In a particular embodiment, an air purifier assembly is disclosed and can include a housing assembly. The air purifier assembly can include a first fluid communication channel within the housing assembly. The first fluid communication channel can have an air inlet formed in a back of the housing assembly and an air outlet formed in a first side of the housing assembly. Further, the air purifier assembly can include a second fluid communication channel within the housing assembly. The second fluid communication channel can have an air inlet formed in a back of the housing assembly and an air outlet formed in a second side of the housing assembly, opposite the first side of the housing.