StacksVerified U.S. regulatory reference

46 CFR §153.352

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
A B/3 or 4 m venting system outlet must:
  1. (a)Discharge vertically upwards; and
  2. (b)Prevent precipitation from entering the vent system.