StacksVerified U.S. regulatory reference

40 CFR §1031.40

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
The following standards apply to turboprop engines with rated output at or above 1,000 kW:
  1. (a)Smoke. Engines of a type or model for which the date of manufacture of the individual engine is on or after January 1, 1984, may not have a characteristic level for smoke number exceeding the following value:
  2. (b)[Reserved]