BlueSky™ Environmental Air Quality Monitors provide trusted results to help protect what's important. Designed for community watch groups, local EPA organizations, fugitive dust monitoring, government agencies, and municipalities, TSI® offers over 50 years or industry experience to support the needs of those looking to utilize low-cost gas sensing (CO, CO₂, NO₂, SO₂, O₃) capabilities, in addition to measuring particulate matter (PM) mass concentrations, temperature, relative humidity (RH), and barometric pressure (BP).ent agencies and environmental organizations, healthcare, hospitals, assisted living campuses, and medical office buildings, schools, industrial manufacturing, factories, power generation and petrochemical plants, hotels, conference centers, shopping malls, and athletic/entertainment arenas, as well as researchers and community groups looking to collect IAQ data.