MR-A ambient air quality monitor (portable) is an instrument for monitoring air quality in the environment. It is an ambient air quality monitor that complies with the Class C method of the "Air and Exhaust Gas Monitoring and Analysis Methods" promulgated by the State Environmental Protection Administration. It can monitor simultaneously. At least four measured gas and particulate matter concentrations required by the environmental protection department. Monitored ambient gases include: SO2, NO2, CO, O3, and particulate matter concentrations include: PM2.5, PM10. It can be expanded to monitor more than thirty kinds of gases such as VOC, H2S, NOX, CH4, HCl, HF, Cl2, NH3, CO2, etc.; dust particles TSP; meteorological parameters: temperature, humidity, atmospheric pressure, wind speed, wind direction, illumination, ultraviolet radiation, Solar radiation, noise, negative oxygen ions, etc. It adopts its own core algorithm to achieve high-precision detection with a resolution of 1ppb.