In a Tuesday, Dec. 21, 2010, Federal Register notice, the EPA announced final amendments to two methods for calculating particulate matter. The action promulgates amendments to Methods 201A and 202 to a add a particle-sizing device to former and revise sample collection to the latter.

The 201A changes allow for sampling of particulate matter with mean aerodynamic diameters less than or equal to 2.5 micrometers (PM2.5).

The final amendments to Method 202 revise the sample collection and recovery procedures of the method to reduce the formation of reaction artifacts that could lead to inaccurate measurements of condensable particulate matter. Additionally, the final amendments to Method 202 eliminate most of the hardware and analytical options in the existing method, thereby increasing the precision of the method and improving the consistency in the measurements obtained between source tests performed under different regulatory authorities.

This action also announced that the EPA is taking no action to affect the already established Jan. 1, 2011 sunset date for the New Source Review (NSR) transition period, during which the federal agency is not requiring that State NSR programs address condensable particulate matter emissions.

The final action is effective on Jan. 1, 2011.

SOURCE: Federal Register