BlueSky? outdoor environmental air quality monitors provide trusted results to help protect what?s important. TSI is excited to announce the expansion of the BlueSky? Outdoor Environmental Air Quality Monitor product line. The newest addition, the BlueSky? Air Quality Monitor Model 8145, is designed to meet the needs of those looking to utilize low-cost gas sensing (CO, CO?, NO?, SO?, O?) capabilities, in addition to measuring particulate matter (PM) mass concentrations, temperature, relative humidity (RH) and barometric pressure (BP).