Motor Vehicle Evaporative Emissions Test Procedures Proposed Technical Amendments June 22, 2006 California Environmental Protection Agency Air Resources Board
What Are Evaporative Emissions? • Hydrocarbon vapors that escape from vehicle’s fuel system • Four types – Running loss – Hot Soak – Diurnal – Refueling
Evap Control System FUEL TANK GAS CAP FILL PIPE CARBON CANISTER VAPOR PURGE LINE
Current Evap Regulations • Evap Tests – 3 -Day Diurnal + High-Temp Hot Soak, Running Loss – Supplemental 2 -Day Diurnal + Hot Soak • ORVR – Adopted 1995 • LEV II Evap – Adopted 1998 – Optional Zero Emission Standard PZEV – In-Use Verification Program
Evap Streamlining • • • Started 1996 Collaborative effort Reduce testing burden No change in stringency Guidance letter sent Dec 2002 U. S. EPA’s Final Rule issued Dec 2005
Proposed Test Procedure Amendments • Evaporative Test Procedures • On-Board Refueling Vapor Recovery • Other minor amendments
Evap Test Procedures • Optional waiver of 2 -Day test – Can be demonstrated by results from 3 -Day and ORVR tests – Other evap tests provide compliance assurances – Reduces costs and testing time • Clarify alternative Running Loss test provisions – Allows ARB to use manuf’s alternative procedure • Allow optional canister precondition method
ORVR Test Procedures • Makes hose disconnection optional – No Compromise in Stringency