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Permeation Data Critique - 1

Permeation Data Critique - 1. Originally, CARB wanted tank permeation reduced by using sulfonation, fluorination, and possibly SELAR - since the thinking was that equipment gas tanks were similar to gas cans. Since then sulfonation has not made the cut – per CARB data

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Permeation Data Critique - 1

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  1. Permeation Data Critique - 1 • Originally, CARB wanted tank permeation reduced by using sulfonation, fluorination, and possibly SELAR - since the thinking was that equipment gas tanks were similar to gas cans. • Since then • sulfonation has not made the cut – per CARB data • fluorination may only work in some cases (see OPEI data for non-effectiveness in roto-molded tanks, as well as for barrier effectiveness variability, and effects of degradation). Many technical issues remain. • SELAR does not work with injection molded tanks The Outdoor Power Equipment Institute 341 South Patrick Street • Alexandria, VA 22314 • 703-549-7600 • 703-549-7604 FAX • www.opei.org

  2. Permeation Data Critique - 2 • although there are many “potential” novel materials, there are no tanks from many of these at the present - hard to evaluate • CARB’s (and Honda’s) best data (around 11 data points collected around March 2003) show that: • if the molding process is “optimized” (not defined at this time) • and a qualitative level of “SL-5+” fluorination is used (extent of barrier parameters not objectively specified) • and not all of the durability requirements that CARB itself has specified are imposed (e.g., no 3000 pressure cycles, etc.) • the best results can range from between 0.4 to over 1 g/m2/day, subject to considerable variability The Outdoor Power Equipment Institute 341 South Patrick Street • Alexandria, VA 22314 • 703-549-7600 • 703-549-7604 FAX • www.opei.org

  3. Permeation Data Critique - 3 • CARB’s own data shows considerable increase in permeation emissions (several-fold) after fluorination: • Could be due to durability aspects • in summary the 2 g/m2/d (at 40 C) rests on weak data The Outdoor Power Equipment Institute 341 South Patrick Street • Alexandria, VA 22314 • 703-549-7600 • 703-549-7604 FAX • www.opei.org

  4. Diurnal Data Critique - 1 • To minimize diurnal emissions CARB proposes to: • pressurize tanks to 4 psig or more • Based on 1 set of CARB tests (one tank) and some recent data from EPA that are not directly comparable • Some manufacturers simply do not feel comfortable using pressurized systems on their products • The minimum cost relief valve to control pressure may be as large as $30.00 or so and this only “controls” set pressure to +/- 25% implying that tanks may have to be designed for pressures as large as 5 psig or more - further exacerbating safety and design risks The Outdoor Power Equipment Institute 341 South Patrick Street • Alexandria, VA 22314 • 703-549-7600 • 703-549-7604 FAX • www.opei.org

  5. Diurnal Data Critique - 2 • use carbon canisters - generally in active mode with canister purge to engine when latter is running • Based on two tests by CARB (working with Delphi) on two engines • The data show widely variable “carburetor” emissions since only emissions remaining in each case (metal tanks, low-perm hose, 95%+ efficient canister etc.) can only be due to carburetor. • Numerous issues associated with active systems not as yet evaluated including significant fire hazard issues when next to catalyst exhausts • possibly require redesigning carburetors. CARB should explicitly consider this possibility in their staff report The Outdoor Power Equipment Institute 341 South Patrick Street • Alexandria, VA 22314 • 703-549-7600 • 703-549-7604 FAX • www.opei.org

  6. Carbon Canister Application • Can not be applied directly to most current tanks with out redesign because the vent location currently is in the cap. This is much more than just adding a vent line to the tank. Liquid vapor separators will be required to prevent liquid fuel from reaching the canister. • Vent location must take into account machine attitude ( +- 20 degrees ANSI) during use and fuel agitation during rough ground use. No liquid fuel can enter the canister to be effective. The Outdoor Power Equipment Institute 341 South Patrick Street • Alexandria, VA 22314 • 703-549-7600 • 703-549-7604 FAX • www.opei.org

  7. Carbon Canister Application • OEM’s know little about carbon canisters and their application to our products. • Vibration • Small OEM’s do not have the testing capability to approve canisters • Break thru venting fire safety issues • Little cost information on systems for our sized units. • Dirty environment issues ( Dust/Debris) • Effect of Power washers The Outdoor Power Equipment Institute 341 South Patrick Street • Alexandria, VA 22314 • 703-549-7600 • 703-549-7604 FAX • www.opei.org

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