The historical data section features past particulate concentrations and internal meteorological conditions of deployed monitors. The data is separated by year to help users more easily obtain historical data. The data is presented so a person can obtain the information by either location or by unit number.
There are two methods to obtain the historical data:

BY UNIT NUMBER - If you know the unit number of the monitor you wish to view, select the “by unit number” drop down selection under the real-time data menu. You may also view the data by clicking on the “real-time data by unit number” to the right. Then select the year of the data you wish to obtain and the unit number.

BY LOCATION – If you know the location of the monitor, select the “by location” drop down selection under the real-time data menu. The select the appropriate year. A map of the United States will appear with the states where units were operated highlighted. Individual states can be selected for a closer view where individual unit numbers can be selected.

The information displayed on the real-time data pages are neither quality checked nor quality assured for accuracy.