[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: 40CFR80.56]

[Page 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. 80.56  Measurement methods for formaldehyde and acetaldehyde.

    (a) Formaldehyde and acetaldehyde will be measured by drawing 
exhaust samples from heated lines through either 2,4-
Dinitrophenylhydrazine (DNPH) impregnated cartridges or impingers filled 
with solutions of DNPH in acetonitrile (ACN) as described in Sec. Sec. 
86.109 and 86.140 of this chapter for formaldehyde analysis. Diluted 
exhaust sample volumes must be at least 15 L for impingers containing 20 
ml of absorbing solution (using more absorbing solution in the impinger 
requires proportionally more gas sample to be taken) and at least 4 L 
for cartridges. As required in Sec. 86.109 of this chapter, two 
impingers or cartridges must be connected in series to detect 
breakthrough of the first impinger or cartridge.
    (b) In addition, sufficient sample must be drawn through the 
collecting cartridges or impingers so that the measured quantity of 
aldehyde is sufficiently greater than the minimum limit of quantitation 
of the test method for at least a portion of the exhaust test procedure. 
The limit of quantitation is determined using the technique defined in 
Sec. 80.55(d).
    (c) Each of the impinger samples are quantitatively transferred to a 
25 mL volumetric flask (5 mL more than the sample impinger volume) and 
brought to volume with ACN. The cartridge samples are eluted in reversed 
direction by gravity feed with 6mL of ACN. The eluate is collected in a 
graduated test tube and made up to the 5mL mark with ACN. Both the 
impinger and cartridge samples must be analyzed by HPLC without 
additional sample preparation.
    (d) The analysis of the aldehyde derivatives collected is 
accomplished with a high performance liquid chromatograph (HPLC). 
Standards consisting of the hydrazone derivative of formaldehyde and 
acetaldehyde are used to determine the response, repeatability, and 
limit of quantitation of the HPLC method chosen for acetaldehyde and 
formaldehyde.
    (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.