Feature

Internet of Things and compensated air quality sensors

By adding air quality sensors to smart building systems, engineers can implement early warning of the buildup of hazardous gases and chemicals, but commercial air quality sensors lack the integrated capabilities required to join a smart building network.

04/02/2019 10:17:13

This deficiency can be overcome by turning to easy-to-use development kits which can add the processing power and wireless capability required.

MOS sensor basics

Metal oxide semiconductor (MOS) type sensors most closely match the monitoring requirements for smart building applications. The devices are compact, relatively inexpensive, can run from batteries, and the detection range matches the typical concentrations of C02 and VOCs (volatile organic compounds) in indoor workplaces.

In operation, the sensing element is heated to several hundred degrees Celsius (°C). The precise temperature determines the element’s selectivity to a specific gas or chemical. The sensitivity depends on the material’s thickness.

The sensors are manufactured with either n-type or p-type semiconductor sensing elements. The sensing element has an electromechanical reaction with the target compound which changes resistivity causing a linear change from a known baseline value.

Read the full article in the February issue of DPA

Written By Sophia Bell

Sophia Bell is the Group Editor of DPA, Connectivity, and PBSI. She joined the team in 2020 as Assistant Editor after achieving a First-Class Honours BA in English Literature and Film Studies from the University of East Anglia. In her current role, she leads the editorial strategy, driving digital growth and ensuring each title continues to deliver trusted, relevant insight for engineering and manufacturing professionals.