StacksVerified U.S. regulatory reference

46 CFR §153.353

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
The discharge point of a B/3 or 4m venting system must be located at least 3m (approx. 10 ft) above the weatherdeck or walkway if:
  1. (a)The discharge is a vertical, unimpeded jet;
  2. (b)The jet has a minimum exit velocity of 30 m/sec (approx. 98.4 ft/sec); and
  3. (c)The high velocity vent has been approved by Commandant (CG-ENG).