Low-Cost Sensor Study to Evaluate NO₂ Sensors

Air agencies and non-governmental organizations need to know the performance capabilities of low-cost sensors. In response, Sonoma Technology evaluated the performance of low-cost NO₂ sensors and assessed their potential usefulness for gradient studies of near-roadway NO₂ concentrations and citizen monitoring of air pollution.<br>

For this evaluation, we developed
<ol>
<li>Protocols involving the design of environmental testing chambers to hold the experimental sensors (instruments).</li>
<li>Experimental designs for simultaneous measurement of target gases and interference with both reference analyzers and the low-cost instruments.</li>
<li>Unique data acquisition, processing, and analytical protocols.</li>
</ol>
As part of this study, we explored
<ul>
<li>Sensor response to NO₂ and ozone.</li>
<li>Cross-sensitivity and relative humidity effects.</li>
<li>Response (such as time lag) to changes in concentration.</li>
</ul>