Guidance and Form Instructions to Parties 


Submitting Diesel Sulfur Accuracy and 


Precision Information for Approval of 


Test Methods by Facility


Transportation and Regional Programs Division 

Office of Transportation and Air Quality 

U.S. Environmental Protection Agency 

May 2005


(Minor Revisions January 22, 2009)


OMB Control Number: 2060-0308


Expiration Date: December 31, 2011


EPA-420-B-09-005 

February 2009 
Disclaimer 

The discussion in this document is intended solely as guidance. The statutory provisions and EPA 

regulations described in this document contain legally binding requirements. This document is not a 

regulation itself, nor does it change or substitute for those provisions and regulations. Thus, it does not 

impose legally binding requirements on EPA, States, or the regulated community. This guidance does not 

confer legal rights or impose legal obligations upon any member of the public. 

While EPA has made every effort to ensure the accuracy of the discussion in this guidance, the obligations 

of the regulated community are determined by statutes, regulations, or other legally binding requirements. 

In the event of a conflict between the discussion in this document and any statute or regulation, this 

document would not be controlling. 

The general description of the application process provided here may not apply to a particular situation. 

Interested parties are free to raise questions about the substance of this guidance and its applicability to a 

particular situation. EPA may adopt approaches on a case-by-case basis that differ from those described 

in this guidance. 

Mention of trade names or commercial products does not constitute endorsement or recommendation for 

their use. 

This is a living document and may be revised periodically without public notice. EPA welcomes public 

input on this document at any time. 
Introduction: On May, 2004, EPA promulgated new requirements for non-road diesel fuel. One of the 

provisions of this final rule, explained in Subpart I of 40 CFR Part 80, requires that each test facility must 

meet specified accuracy and precision criteria with their chosen test method for sulfur in on-road or nonroad diesel fuel additives and/or diesel fuel. Evidence of having met these requirements must be 

submitted to and approved by the Agency before using the method to make measurements for 

demonstrating compliance. There are separate accuracy and precision criteria for diesel fuels and 

additives subject to the two sulfur standards --15 ppm and 500 ppm. 

Depending on your test facility situation, you may be required just to meet the 15 ppm diesel sulfur 

accuracy and precision criteria, you may choose to meet the 500 ppm diesel sulfur accuracy and precision 

criteria, or may be required to meet both of these accuracy and precision criteria. For diesel fuel at the 

500 ppm sulfur level, if your test facility has chosen to use the designated test method, ASTM D 2622-03, 

or any of the following alternative test methods, ASTM D 4294-03, ASTM D 5453-03a, or ASTM D 3120-

03a with correlation to the designated test method, it is not necessary for your test facility to qualify these 

methods for precision or accuracy. 

40 CFR § 80.520(a)(1) explains the 15 ppm sulfur standard for motor vehicle diesel fuel and fuel additives. 

40CFR § 80.510(b)(1)(i) and § 80.510(c) explains the 15 ppm sulfur standard for Non-road Locomotive 

Marine(NRLM) diesel fuel and fuel additives. 40 CFR § 80.520(c) explains the 500 ppm sulfur standard 

for motor vehicle diesel fuel. 40 CFR § 80.510(a) explains the 500 ppm sulfur standard for NRLM diesel 

fuel. 40 CFR § 80.584 explains the actual accuracy and precision criteria for the applicable standards 

above. 40 CFR § 80.585 explains both the requirement that the criteria must be met on a facility-specific 

basis and a description of the process by which methods may be approved. The following guidance 

applies to any party applying to EPA for such approval of their test method at their testing facility. This 

guidance deals only with the approval of test methods at a testing facility for measuring sulfur in diesel fuel 

additives or sulfur in diesel fuel. 

The discussions of the applicable regulations in this document are not verbatim. The reader is 

encouraged to read and become familiar with the applicable regulations of Subpart I of 40 CFR Part 80. 

These instructions are intended to help a test facility qualify a method for the measurement of sulfur in 

diesel motor fuel or diesel motor fuel additives, as well as, to help facilitate the timely review and approval 

of each test facility’s method. 

Applicable Dates: These requirements for method qualification under § 80.585 become effective on 

December 27, 2004. 

Note: Please see Part I for instructions on use of a spreadsheet template provided by the Agency for 

determining compliance with the accuracy and precision criteria of § 80.584. We encourage parties to use 

this spreadsheet to structure their development of the information and data needed for a method 

qualification application and to submit it to the Agency in order to expedite the review and approval 

process. Please see Part II for submission instructions. 

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Part I - Instructions for use of spreadsheet for evaluating method precision and accuracy. 

I. Precision demonstration for motor vehicle diesel fuel and diesel fuel additives subject to 

the 15 ppm sulfur standard. 

Precision Criteria, § 80.584(a)(1) - a standard deviation less than 0.72 ppm, computed from the results of 

a minimum of 20 repeat tests made over 20 days on samples taken from a single homogeneous 

commercially available diesel fuel with a sulfur content in the range of 5-15 ppm. The 20 results must be a 

series of tests with a sequential record of analyses and no omissions.1 

A. In the workbook entitled “Sulfur Test Method Template”, locate the worksheet entitled, “15 ppm S 

Precision”. Enter data in the light shaded green areas of the worksheet. For an example of the 

“15 ppm S Precision” worksheet with data completely entered, please see the worksheet entitled, 

“EX - 15 ppm S Precision”. 

Notes: 

1. Test results must be reported in parts per million (ppm) to the number of significant digits 

specified in the method description or, if no such precision is indicated, to as many digits 

to the right of the decimal point as appear on the instrument readout up to three. 

2. The date and time of each test measurement must be reported. 

3. Please include the laboratory test identification number for each test result. 

B. After entering the data into the light shaded green area of the “15 ppm S Precision” worksheet, go 

to the “File” menu at the top of the screen and select “Save” to save your data. Once all the data 

are entered into the “15 ppm S Precision” worksheet, the standard deviation of the data set 

(located in cell B18), and an indication as to whether the 15 ppm sulfur precision criterion are met 

will be determined by the worksheet. The indication of “PASSED” or “FAILED” is located in cell 

B17 in the worksheet, after the question, “Is 15 ppm Sulfur Precision Criterion Met?”. If the 

worksheet is missing required data, an indication of “REQUIRED DATA MISSING” will appear 

after this question. There is a QC data entry check for each test result in column E (i.e., if data is 

entered in a test result cell, an indication of “OK” will appear next to that cell, but if no data is 

entered in a test result cell, an indication of “DATA REQUIRED IN CELL #” will appear next to that 

cell). Note: If the applicant wishes to include more than the 20 minimum tests, please report the 

additional data by adding rows to the spreadsheet.2 

1 A laboratory may exclude a given sample or test result only if the exclusion is for a valid reason 

under good laboratory practices and it maintains records regarding the sample and test results and the 

reason for excluding them. 

2 Additional rows may be inserted to accommodate the extra data points. If these rows are added 

in the middle (say around row 25), the equations that analyze the data will be automatically adjusted. If 

difficulties are encountered in doing this, please call for help. 

2 
II. Accuracy demonstration for motor vehicle diesel fuel and diesel fuel additives subject to 

the 15 ppm sulfur standard. 

Accuracy Criterion - 1. The arithmetic average of a continuous series of at least 10 tests 

performed on a commercially available gravimetric sulfur standard 

(CAGSS) in the range of 1-10 ppm sulfur shall not differ from the 

accepted reference value of that standard by more than 0.54 ppm sulfur.3 

2. The arithmetic average of a continuous series of at least 10 tests 

performed on a CAGSS in the range of 10-20 ppm sulfur shall not differ 

from the accepted reference value of that standard by more than 0.54 

ppm sulfur.4 

A. Locate the worksheet entitled, “15 ppm S Accuracy”. Enter data in the light shaded green areas of 

the worksheet. For an example of the “15 ppm S Accuracy” worksheet with data completely 

entered, please see the worksheet entitled, “EX - 15 ppm S Accuracy”. 

Notes: 

1. Test results must be reported in parts per million (ppm) to the number of digits specified in 

the method description or, if no such precision is indicated, to as many digits to the right of 

the decimal point as appear on the instrument readout up to three. 

2. It is recommended that the date and time of each test measurement be reported. 

3. Please include the laboratory test identification number for each test result. 

4. In the appropriate rows, enter the “Vendor Name of Gravimetric Standard”, “Lot 

Identification Number of Gravimetric Standard”, and “Accepted Reference Value of the 

Gravimetric Standard (ppm)” in parts per million for both the 1-10 ppm and 10-20 ppm 

sulfur gravimetric standards. 

5. Since the Test Method and Laboratory Identification information for this demonstration are 

the same as the Test Method and Laboratory Identification information in the “15 ppm S 

precision” worksheet, for your convenience, this information is automatically referenced 

from the “15 ppm S Precision” worksheet. 

B. After entering the data into the light shaded green area of the worksheet as described above, go 

to the “File” menu at the top of the screen and select “Save” to save all of the entered data. Once 

all data are entered into the “15 ppm S Accuracy” worksheet, this worksheet will calculate the 

arithmetic average for both the 1-10 ppm sulfur data set (located in cell B20) and the 10-20 ppm 

sulfur data set (located in cell I20). This worksheet will also calculate the difference between the 

arithmetic average of the data set and the accepted reference value of each respective 

gravimetric standard (located in cell B24 for the 1-10 ppm accuracy demonstration & located in 

cell I24 for the 10-20 ppm accuracy demonstration). This worksheet will indicate whether the 15 

ppm sulfur accuracy criteria are met for the candidate test method by saying “PASSED” or 

“FAILED” in the cell after the questions, “Is 1-10 ppm Sulfur Accuracy Criterion Met?” (located in 

cell B19) and “Is 10-20 ppm Sulfur Accuracy Criterion Met?” (located in cell I19). Both of these 

accuracy criteria must be met in order for the test method to be considered to have met the 15 

ppm accuracy criteria. If the worksheet is missing required data, an indication of “REQUIRED 

DATA MISSING” will appear after the applicable question. There is a QC data entry check for 

each test result in column E and column L (i.e., if data is entered in a test result cell, an indication 

of “OK” will appear next to that cell, but if no data is entered in a test result cell, an indication of 

“DATA REQUIRED IN CELL #” will appear next to that cell). There is also a QC data entry check 

3 Individual test results shall be compensated for any known chemical interferences. 

4 Individual test results shall be compensated for any known chemical interferences. 

3 
on the concentration of the gravimetric standard in cell E23 and cell L23 (i.e., for either the 1 to 10 

ppm sulfur accuracy demonstration or 10 to 20 ppm sulfur accuracy demonstration, if the 

concentration of gravimetric standard falls within the applicable concentration range, an indication 

of “OK” will appear in the respective cell, if the concentration of the gravimetric standard falls 

below the applicable concentration range, an indication of “ARV TOO LOW IN 

CONCENTRATION” will appear in the respective cell, if the concentration of the gravimetric 

standard is above the applicable concentration range, an indication of “ARV TOO HIGH IN 

CONCENTRATION” will appear in the respective cell). Note: If the applicant wishes to include 

more than the 10 minimum tests, please report the additional data by inserting rows into the 

spreadsheet.5 

III. Precision demonstration for motor vehicle diesel fuel subject to the 500 ppm sulfur 

standard. 

Precision Criterion, § 80.584(a)(2) - a standard deviation less than 9.68 ppm, computed from the results 

of a minimum of 20 repeat tests made over 20 days on samples taken from a single homogeneous 

commercially available diesel fuel (SHCADF) with a sulfur content in the range of 200-500 ppm. The 20 

results must be a series of tests with a sequential record of analyses and no omissions.6 

A. Locate the worksheet entitled, “500 ppm S Precision”. Follow the instructions for Section I above, 

but enter the data for the 500ppm precision demonstration rather than that for the 15ppm 

demonstration. For an example of the “500 ppm S Precision” worksheet with data completely 

entered, please see the worksheet entitled, “EX - 500 ppm S Precision”. 

5 Additional rows may be inserted to accommodate the extra data points. If these rows are 

inserted in the middle of the range (say after row 30) the equations for the average and other functions will 

be automatically adjusted. Extra rows inserted for one of the two standard levels, while appearing in the 

range for the other standard level, will not affect the calculations for the level where no data were added. 

6 A laboratory may exclude a given sample or test result only if the exclusion is for a valid reason 

under good laboratory practices and it maintains records regarding the sample and test results and the 

reason for excluding them. 

4 
IV. Accuracy demonstration for motor vehicle diesel fuel subject to the 500 ppm sulfur 

standard. 

Accuracy Criterion - 1. The arithmetic average of a continuous series of at least 10 tests 

performed on a commercially available gravimetric sulfur standard 

(CAGSS) in the range of 100-200 ppm sulfur shall not differ from the 

accepted reference value of that standard by more than 7.26 ppm sulfur.7 

2. The arithmetic average of a continuous series of at least 10 tests 

performed on a CAGSS in the range of 400-500 ppm sulfur shall not 

differ from the accepted reference value of that standard by more than 

7.26 ppm sulfur.8 

A. Locate the worksheet entitled, “500 ppm S Accuracy”. Follow the instructions for section II above, 

but enter the data for the 500ppm accuracy demonstration rather than that for the 15ppm 

demonstration. For an example of the “500 ppm S Accuracy” worksheet with data completely 

entered, please see the worksheet entitled, “EX - 500 ppm S Accuracy”. 

7 Individual test results shall be compensated for any known chemical interferences. 

8 Individual test results shall be compensated for any known chemical interferences. 

5 
PART II - Instructions for submission of Accuracy and Precision data to Agency for Approval 

I. For each test facility that wishes to have a test method approved, the following information 

must be submitted to the Agency for approval: 

A. 40 CFR 80.585(a). For methods that are approved by a voluntary consensus-based organization 

standards body (VCSB), such as the American Society for Testing and Materials (ASTM) or 

International Standards Organization (ISO), each individual test facility must submit the 

information for accuracy and precision criteria specified under § 80.584 (Please use instructions in 

Part I of this guidance). The approval of the test method is limited to the single test facility that 

performed the testing for accuracy and precision. The individual facility must submit the accuracy 

and precision results for each method, including information on the date and time of each test 

measurement to demonstrate precision, following procedures established by the Administrator. 

B. 40 CFR 80.585(b). For methods that are not approved by a VCSB, for such a method to be 

approved, the following information must be submitted to the Administrator by each test facility for 

each test method that it wishes to have approved: 

1. Full test method documentation, including a description of the technology and/or 

instrumentation that makes the method functional. 

2. Information demonstrating that the test method meets the applicable accuracy and 

precision criteria of § 80.584, including information on the date and time of each test 

measurement to demonstrate precision (Please use instructions in Part I of this guidance). 

3. If requested by EPA, test results from use of the test method to analyze samples of 

commercially available fuel provided by EPA. 

4. Any additional information requested by the Administrator and considered necessary for 

deciding whether to approve the test method. 

C. 40 CFR 80.585(c). Sample Retention. Samples used for precision and accuracy determination 

must be retained for 90 days. 

D. Confidential Business Information Claim. You may claim the information you submit as 

confidential business information (CBI) by clearly marking your submission. Please be sure to 

indicate your CBI claim where asked on the spreadsheet and clearly indicate that your submission 

contains information claimed as CBI in your cover letter. If no such written claim is made, then the 

information you submit may be made available to the public by EPA without further notice. EPA’s 

regulations regarding CBI are at 40 CFR Part 2. 

E. Please send one paper hard copy of your applicable information described above that includes a 

cover memo with your signature, along with a 3.5 inch floppy disk or compact disk containing the 

accuracy and precision data in the spreadsheet described above by overnight mail or courier 

service to the address below. 

Joe Sopata, Chemist

United States Environmental Protection Agency

Fuels Program Support Group

Transportation and Regional Programs Division

1310 L Street, N.W, (6406J), 6th Floor, Room 627Q

Washington, D.C. 20005

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F. 40 CFR 585(d). EPA Approval. 

1. Within 90 days of receipt of all materials required to be submitted under 40 CFR 80.585(a) 

or (b), the Administrator shall determine whether the test method is approved. 

2. If the Administrator denies approval of the test method, within 90 days of receipt of all 

materials required to be submitted under 40 CFR 80.585(a) or (b), the Administrator will 

notify the applicant of the reasons for not approving the method. If the Administrator does 

not notify the applicant within 90 days of receipt of the application, that the test method is 

not approved, then the test method shall be deemed approved. 

3. If the Administrator finds that and individual test facility has provided false or inaccurate 

information under 40 CFR 80.585, upon notice from the Administrator the approval shall 

be void ab initio. 

4. Non-VCSB test method/test facility approval shall be valid for five years from the date of 

approval by the Administrator and shall not be extended. If the method is later approved 

by a VCSB, the approval shall remain valid so long as the conditions of 40 CFR 80.585(a) 

are met. 

G. 40 CFR 80.585(e). Quality Assurance procedures for sulfur measurement instrumentation. A test 

method shall not be considered a test using an approved test method unless the following quality 

control procedures are performed separately for each instrument to make measurements: 

1. Follow all mandatory provisions of ASTM D 6299-02 and construct control charts from the 

mandatory quality control testing prescribed in paragraph 7.1 of the reference method, 

following guidelines under A 1.5.1 for individual observation charts and A 1.5.2 for moving 

range charts.9 

2. Follow paragraph 7.3.1 of ASTM D 6299-02 to check standards using a reference material 

at least monthly or following any major change to the laboratory equipment or test 

procedure. Any deviation from the accepted reference value of a check standard greater 

than 1.44 ppm (for diesel fuel subject to the 15 ppm sulfur standard) or 19.36 ppm (for 

diesel fuel subject to the 500 ppm sulfur standard) must be investigated. 

3. Samples of test batches must be retained for 30 days or the period equal to the interval 

between quality control sample tests, whichever is longer. 

9 The Director of the Federal Register approved the incorporation by reference of ASTM D 6299-

02, Standard Practice for Applying Statistical Quality Assurance Techniques to Evaluate Analytical 

Measurement System Performance, as prescribed in 5 U.S.C. 552(a) and 1 CFR Part 51. Anyone may 

purchase copies of this standard from the American Society for Testing and Materials, 100 Barr Harbor 

Dr., West Conshohocken, PA 19428. Anyone may inspect copies at the U.S. EPA, Air and Radiation 

Docket and Information Center, 1301 Constitution Ave., N.W., Room B102, EPA West Building, 

Washington, D.C. 20460 or at the National Archives and Records Administration (NARA). For information 

on the availability of this material at NARA, call 202-741-6030 or go to: 

http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html. 

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4. Upon discovery of any quality control testing violation of paragraph A 1.5.1.3 or A 1.5.2.1 

of ASTM D 6299-02, or any check standard deviation greater than 1.44 ppm (for diesel 

fuel subject to the 15 ppm sulfur standard) or 19.36 ppm (for diesel fuel subject to the 500 

ppm sulfur standard), conduct an investigation into the cause or such violation or 

deviation and, after restoring method performance to statistical control, retest retained 

samples from batches originally tested since the last satisfactory quality control material 

or check standard testing occasion. 

H. 40 CFR 80.586. Record retention requirements for approved test methods. Each individual test 

facility must retain records related to the establishment of accuracy and precision values, all test 

method documentation, and any quality control test and analysis under title 40 CFR sections 

80.584 and 80.585 for five years. 

EPA Contact: 

Joe Sopata 

(202) 343-9034 

Fax: (202) 343-2801 

Email: sopata.joe@epa.gov 

OMB Control No. 2060-0308

Approval expires: December 31, 2011

The public reporting and recordkeeping burden for this collection of information is estimated to average 

180 hours per response. Send comments on the Agency’s need for this information, the accuracy of 

the providing burden estimates, and any suggested methods for minimizing respondent burden, 

including through the use of automated collection techniques to the Director, Collection Strategies 

Division, U.S. Environmental Protection Agency (2822T), 1200 Pennsylvania Ave., NW, Washington, 

D.C. 20460. Include the OMB control number in any correspondence. Do not send the completed form 

to this address. 

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