Smoke School Information in South Carolina

South Carolina Acceptance Status for VirtualOpacity^® — EPA ALT-152A

Accepted.

South Carolina Visible Emissions / Opacity Standard

The opacity limit for South Carolina is Pre-Feb 11, 1971 sources: 40% opacity; sources constructed on/after Feb 11, 1971: 20%; sootblowing exceedance <=6 min per hour and <=24 min per 24 hr, sootblowing max 60%; process industries (Std. No. 4): 20% stack opacity for most categories, as established under S.C. Code Regs. 61-62.5, Standard No. 1, Sec. I.A (pre-Feb 11, 1971) and I.B (on/after Feb 11, 1971); Method 9 per I.D.

Compliance is demonstrated via EPA Reference Method 9 (40 CFR 60, Appendix A, as revised July 1, 1986).

Averaging period: Exception for soot blowing: may exceed standard for ≤6 min per 1-hour period, ≤24 min per 24-hour period; soot blowing emissions capped at 60%

South Carolina's general visible emissions standard is split by construction date: 40% for pre-February 11, 1971 sources and 20% for sources built on or after that date. The soot blowing exception allows temporary exceedances up to 60% but limits aggregate duration. An exception from the 20% standard is available if the source demonstrates PM mass compliance and no NAAQS impact (can operate at up to 40% opacity).

Last verified July 8, 2026

Note: Regulations change — always verify current requirements with your state's air quality agency before making compliance decisions. This page is for informational purposes and is not legal advice; consult a qualified attorney or environmental compliance professional for guidance specific to your facility.