### Question
How does the law define PM–10?


### Answer
Under *42 U.S.C. § 7602*, **PM–10** is defined as:

> particulate matter with an aerodynamic diameter less than or equal to a nominal ten micrometers, as measured by such method as the Administrator may determine

#### Citation:
  - *42 U.S.C. § 7602*
  - Heading: **SUBCHAPTER I-PROGRAMS AND ACTIVITIES > Subchapter Referred to in Other Sections**

