A system and method for initial calibration of an air-quality sensor device. The method includes establishing at least a reference response to an environmental condition based on a response of at least one calibrated detector to the environmental condition; establishing at least a sensor response to the environmental condition based on the response of at least one uncalibrated detector to the environmental condition; developing, based on the established sensor response, at least a sensor response slope; determining, based on the established reference response, the established sensor response, and the developed sensor response slope, at least a corrected response; and returning the corrected response.