{"data":{"id":"us-va/9vac5-30-68","jurisdiction":"us-va","citation":"9VAC5-30-68","heading":"Particulate matter (PM2.5)","body":"A. The national primary ambient air quality standards for PM2.5 are 9.0 micrograms per cubic meter (µg/m3) annual arithmetic mean concentration and 35 µg/m3 24-hour average concentration measured in the ambient air as PM2.5 (particles with an aerodynamic diameter less than or equal to a nominal 2.5 micrometers) by either:\n\n1. A reference method based on Appendix L to 40 CFR Part 50 and designated in accordance with 40 CFR Part 53; or\n\n2. An equivalent method designated in accordance with 40 CFR Part 53.\n\nB. The primary annual PM2.5 standard is met when the annual arithmetic mean concentration, as determined in accordance with Appendix N to 40 CFR Part 50, is less than or equal to 9.0 µg/m3.\n\nC. The primary 24-hour PM2.5 standard is met when the 98th percentile 24-hour concentration, as determined in accordance with Appendix N to 40 CFR Part 50, is less than or equal to 35 µg/m3.","path":["Title 9. Environment","Agency 5. State Air Pollution Control Board","Chapter 30. Ambient Air Quality Standards"],"source_url":"https://law.lis.virginia.gov/admincode/title9/agency5/chapter30/section68/","current_through":"2026 Regular Session (effective July 1, 2026)","vintage":"","retrieved_at":"2026-09-14T04:48:03Z","sha256":"de289cdc426708d206c01231375a9dcef4f2f9d70180631734375495d3e80cd8","source_id":"us-va-vac","stale":false,"prev":"us-va/9vac5-30-67","next":"us-va/9vac5-30-70"},"notice":"GroundRules: Original legal text. Not legal advice."}