[Code of Federal Regulations]
[Title 40, Volume 16]
[Revised as of July 1, 2008]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR80.55]

[Page 687-688]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 80_REGULATION OF FUELS AND FUEL ADDITIVES--Table of Contents
 
                     Subpart D_Reformulated Gasoline
 
Sec. 80.55  Measurement methods for benzene and 1,3-butadiene.

    (a) Sampling for benzene and 1,3-butadiene must be accomplished by 
bag sampling as used for total hydrocarbons determination. This 
procedure is detailed in 40 CFR 86.109.
    (b) Benzene and 1,3-butadiene must be analyzed by gas 
chromatography. Expected values for benzene and 1,3-butadiene in bag 
samples for the baseline fuel are 4.0 ppm and 0.30 ppm respectively. At 
least three standards ranging from at minimum 50% to 150% of these 
expected values must be used to calibrate the detector. An additional 
standard of at most 0.01 ppm must also be measured to determine the 
required limit of quantification as described in paragraph (d) of this 
section.
    (c) The sample injection size used in the chromatograph must be 
sufficient to be above the laboratory determined limit of quantification 
(LOQ) as defined in paragraph (d) of this section for at least one of 
the bag samples. A control chart of the measurements of the standards 
used to determine the response, repeatability, and limit of quantitation 
of the instrumental method for 1,3-butadiene and benzene must be 
reported.
    (d) As in all types of sampling and analysis procedures, good 
laboratory practices must be used. See, Lawrence, Principals of 
Environmental Analysis, 55 Analytical Chemistry 14, at 2210-2218 (1983) 
(copies may be obtained from the publisher, American Chemical Society, 
1155 16th Street NW., Washington, DC 20036). Reporting reproducibility 
control charts and limits of detection measurements are integral 
procedures

[[Page 688]]

to assess the validity of the chosen analytical method. The 
repeatability of the test method must be determined by measuring a 
standard periodically during testing and recording the measured values 
on a control chart. The control chart shows the error between the 
measured standard and the prepared standard concentration for the 
periodic testing. The error between the measured standard and the actual 
standard indicates the uncertainty in the analysis. The limit of 
detection (LOD) is determined by repeatedly measuring a blank and a 
standard prepared at a concentration near an assumed value of the limit 
of detection. If the average concentration minus the average of the 
blanks is greater than three standard deviations of these measurements, 
then the limit of detection is at least as low as the prepared standard. 
The limit of quantitation (LOQ) is defined as ten times the standard 
deviation of these measurements. This quantity defines the amount of 
sample required to be measured for a valid analysis.
    (e) Other sampling and analytical techniques will be allowed if they 
can be proven to have equal specificity and equal or better limits of 
quantitation. Data from alternative methods that can be demonstrated to 
have equivalent or superior limits of detection, precision, and accuracy 
may be accepted by the Administrator with individual prior approval.