{"data":{"id":"us-va/9vac5-30-15","jurisdiction":"us-va","citation":"9VAC5-30-15","heading":"Reference conditions","body":"All measurements of air quality that are expressed as mass per unit volume (e.g., micrograms per cubic meter) other than for the particulate matter (PM2.5) standards contained in 9VAC5-30-65, 9VAC5-30-66, and 9VAC5-30-67, and lead standards contained in 9VAC5-30-80 shall be corrected to a reference temperature of 25°C and a reference pressure of 760 millimeters of mercury (1,013.2 millibars). Measurements of PM2.5 for purposes of comparison to the standards contained in 9VAC5-30-65, 9VAC5-30-66, and 9VAC5-30-67 and of lead for purposes of comparison to the standards contained in 9VAC5-30-80 shall be reported based on actual ambient air volume measured at the actual ambient temperature and pressure at the monitoring site during the measurement period.","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/section15/","current_through":"2026 Regular Session (effective July 1, 2026)","vintage":"","retrieved_at":"2026-09-14T04:48:03Z","sha256":"8b85416d521c079d780d02a7a2662c6c3a9d3afff247ce6cf66ae3ba3b4e860f","source_id":"us-va-vac","stale":false,"prev":"us-va/9vac5-30-10","next":"us-va/9vac5-30-30"},"notice":"GroundRules: Original legal text. Not legal advice."}