In 2006, Nye County experienced 0 days of unhealthy air quality and 1 days in which air quality was considered unhealthy for sensitive groups. Of the 273 days monitored, most days fell in the good (250 days) to moderate (22 days) range. Nye County experiences PM10 pollutants in the air almost daily, this is particulate matter smaller than 10 micrometers. Nye County had an annual mean of 46 in 2004, which was successfully lowered to 25 in 2005 but went up in 2006 to 34. The biggest culprit of PM10 pollutants is dust, due to unpaved roads and construction in the county, especially in the booming town of Pahrump. Nye County has been within the attainment status for the annual mean of PM10 allowed by the EPA of 50, for good air quality, but periodically fails to meet the 24-hour standard of 150. The air quality index chart to the right shows the classification ranges. Nye County is in the attainment status in all other areas of emissions.