**UNITED STATES ENVIRONMENTAL PROTECTION AGENCY** NATIONAL VEHICLE AND FUEL EMISSIONS LABORATORY

2000 TRAVERWOOD DRIVE ANN ARBOR, MI 48105
- 2498

OFFICE OF AIR AND RADIATION April 30 , 2013 MEMORANDUM SUBJECT: Meeting with American Petroleum Institute (API) Test Methodologies Workgroup FROM: Joe Sopata, Chemist

USEPA/ OAR/OTAQ/CD/FCC THROUGH: John Weihrauch, Center Director

USEPA/OAR/OTAQ/CD/FCC TO: EPA Docket # EPA
- HQ
- OAR
- 2011
- 0135 This me mo documents a meeting held on Ap ril 18, 2013 between representatives of API Test Methodologies Workgroup an d the United States Environmental Protection Agency ( EPA ) to discuss EPA’s Performance Based Anal yt ical Test Method Approach (PBATMA) included in the proposed rule entitled, “Contr ol of Air Pollution from Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards” (Tier 3)
. The meeting attendees from API Test Methodologies Workgroup included David Lax (API), Frank Disanzo, (Exxonmobil), Kathry n Brtko (BP), Janice Raburn (BP), Kishore Nadkarni, Barbara Schroeder (Shell), Richard Stanley (RMS Statistics), Al Verstuy ft (Al Verstuy ft Consulting), Alex Lau (TCL
- Consulting), John Rizzo (Marathon Petroleum), Peg Broughton (Marathon Petroleum), and from EPA included Joe Sopata and John Weihrauch
. The PBATMA discussion topics included background, proposed qualification criterion, statistical quality control requirements, implementation dates and Agency approval options which are presented in detail the preamble and regulations of the T ier 3 proposal. T he API Test Methodologies Workgroup requested that EPA provide flow chart examples of qualification requirements for Absolute Fuel Parameter s and Method Defined Fuel Parameters. These flowcharts are attached. These flow charts are not intended to cover allaspects of the Performance Based Anal yt ical Test Method Approach proposed requirements. EPA encourage s review of both the

preamble and re gulations for details on the PBATMA proposal not covered in these flow charts.

## Flow Chart **Example :**  **Absolute Fuel Parameter (Absolute)**  **- Sulfur in Gasoline**  Note : EPA proposes that fuel parameters categorized as “ Absolute ” are s ulfur in g asoline and s ulfur in b utane ( VCSB

– Voluntary Consensus Standards Body )

YES YES

NO NO

NO

YES Is Alternative Test Method a Voluntary Consensus Standard Body (VCSB Method)? **Precision**
- the maximum allowable standard deviation of 20 test results on a 10 ppm gasoline would be 0.95 ppm. **Accuracy**

– the average of 10 consecutive results on a 1
- 10 ppm gravimetric sulf ur standard cannot be more than 0.71 ppm and the average of 10 consecutive results on a 10
- 20 ppm gravimetric sulfur standard cannot more than 1.00 ppm Method Qualified

Lab determines if ASTM D6708 reveals that sample
- specific biases cannot be determined as random?
Method Disqualified. Method Disqualified

## Flow Chart E **xample :**  **Method -**  **Defined Fuel**  **Parameter (Method**  **- Defined)** 

**Aromatics in Gasoline:** Note : EPA proposes that all other fuel parameters besides sulfur in gasoline and sulfur in b utane currently designated in our gasoline and diesel fuel programs are Method
- D efined ( VCSB

– Voluntary Consensus Standards Body )

YES NO

YES NO YES NO Obtain use of a Reference Installation of Designated Test Method (DM): 1) DM near middle distribution of industry monthly inter
- laboratory

crosscheck program. 2) DM has been shown to be in statistical control. (Both for 5 months) Precision
- the maximum allowable standard deviation of 20 test results on a 32 volume percent aromatics gasoline would be 0.70 volume percent Is Alternative Test Method a Voluntary Consensus Standard Body (VCSB) Method?

VCSB determines if use of ASTM D6708 yields a null result compared to designated test method (DM)?( ****** ) Lab determines if ASTM D6708 reveals that sample
specific biases cannot be determined as random?

Use Alternative Test Method result w/o correlation. VCSB uses

ASTM D6708 to determine correlation equation to DM. Method Disqualified

. Same as ****** but

Lab also determines if the cross method reproducibility (Rcm) is ≤ 70% of published R of DM.