The major objectives of this project are to make a plan for inter-comparisons of particulate matter (PM, including PM10 and PM2.5) monitoring instruments, to confirm the comparability of these PM monitors, and to establish a local PM monitoring database. The current reference methods for measuring the mass concentration of PM in ambient air are based on a 24-hour collection followed by gravimetric analysis. However, continuous automated monitors are required in the monitoring networks to provide real-time information. These automated monitors are based on different operation principles than the reference method. Therefore it is necessary to demonstrate that the automated instruments can produce results that are comparable with the reference method. This is mainly done by executing parallel comparative measurements between collocated reference and automated monitors. Through comprehensive statistical analysis, precision and regression parameters will be evaluated to examine the degree of equivalence for the PM monitors that are used in this study. The reliability of reported monitoring data can be enhanced upon the demonstration of equivalence and comparability. The tasks in this project can be divided into four parts: (1) Sketch a program for inter-comparisons of PM10 and PM2.5 monitoring instruments; (2) Conduct statistical analysis for the resulting comparison data to examine measurement comparability; (3) Make a draft of the Purchasing Policy ＆ Procedure Guide for PM monitoring instruments; (4) Propose a mechanism to help EPA establish internationally recognized metrological traceability on ozone and particulate matter measurement. The accuracy of measuring data is based on the metrological traceability. The last task of this project is to propose the practical plans for EPA to build standard systems and establish the metrological traceability for ozone and particulate matter measurements.

Ozone standard;Fine particulate matter;Intercomparison of monitoring instruments