Ozone monitoring may be accomplished with the use of instruments using the measurement of UV light to determine ozone concentrations. For example, the 2B Technologies Model 202 Ozone Monitor™ designed to enable accurate and precise measurements of ozone ranging from low ppb (precision of ~1 ppb) up to 100,000 ppb (0-100 ppm). While portable, most ozone monitors are housed in fixed station monitoring sites and are operated by air management districts and states, NPS, and other agencies to measure and compare ozone levels with the NAAQS for ozone.