www.safetyandhealthmagazine.com/articles/air-quality-monitor-2

Air quality monitor

January 24, 2011
The Comfort Chek 500 handheld carbon dioxide air quality monitor comes equipped with a sensor that measures and displays 0-5,000 ppm, in addition to temperature and relative humidity sensors. The product is economical and features a run time of up to 24 hours, data logging up to 26,000 data points, and a USB output for remote data download.

Bacharach Inc.