Evaporative Emission Control for Gasoline Boat Fuel Systems

1. Evaporative Emission Control for Gasoline Boat Fuel Systems Mike Samulski U.S. Environmental Protection Agency International Boatbuilders’ Exhibition & Conference October 20, 2005

2. Evaporative Emissions from Boats Refueling and spillage Diurnal, hot soak, and running loss Permeation through fuel tank and hoses

3. EPA’s Role • Clean Air Act (amended 1990) • section 213 applies to nonroad engines/equipment • “...greatest degree of emission reduction achievable through the application of technology...” • consider cost, lead time, safety, energy • Past Efforts • implemented exhaust emission standards for the majority of nonroad engines • evaporative emission standards for some applications • recreational vehicles, Large SI (>25 hp) • originally proposed evaporative emission standards for marine in August 2002, but have not finalized

4. Rulemaking Plans • Scope • exhaust and evaporative emissions • gasoline-powered engines/vessels • build on 2002 NPRM • Schedule • anticipate proposal this spring • final rule ~ 1 year later • Marine Evaporative Emissions • tank permeation • hose permeation • diurnal breathing losses

5. Rulemaking Process • gather information • meet with stakeholders • publish “Final Rulemaking” Implement FRM • publish “Notice of Proposed Rulemaking” • lead time • certification Public Comment NPRM • public hearing • written comment period Pre- Proposal

6. Tank Permeation Control • High Density Polyethylene (HDPE) • portable, PWC, and some installed fuel tanks • fluorination, sulfonation, Selar, multi-layer, alternative materials • Cross-Link PE • installed fuel tanks (low volume production) • barrier coating, multi-layer roto-molding, alternative materials, alternative constructions • Fiberglass • built-in installed fuel tanks • multi-layer construction • (Metal does not permeate)

7. Hose Permeation Control • Multi-layer fuel hose • barriers used today in non-marine applications (Teflon, THV, FKM, etc.) • marine barrier hose available as well • can add barriers to current marine constructions • > 95% reduction in permeation possible • Evaluating contribution of vapor versus fuel hose barrier layer reinforcement rubber cover

8. Diurnal Breathing Loss Control • Portable fuel tanks • currently have manual seal without pressure relief • could use self sealing caps (1 way valve) • PWC • already have sealed systems with pressure relief valves • 1 psi ~ 50% reduction in-use from an open system • Larger fuel tanks • carbon canister in vent line • > 60% reduction with passive purge • negligible back-pressure • other technologies include • bladder fuel tanks • active purge canisters

9. Other Evaporative Emissions • Venting emissions • running loss, hot soak, effusion • also reduced somewhat by diurnal control systems • Refueling emissions • vapor displacement • spillage • both air and water pollution issue • could be reduced through fuel system design • configure fill neck for fuel shut-off before overflow • valve to prevent liquid fuel from entering vent line 320

10. Questions? www.epa.gov/otaq/marinesi.htm Mike Samulski samulski.michael@epa.gov