[Code of Federal Regulations]
[Title 40, Volume 31]
[Revised as of July 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR1048.245]

[Page 569]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 1048_CONTROL OF EMISSIONS FROM NEW, LARGE NONROAD 
SPARK-IGNITION ENGINES--Table of Contents
 
                  Subpart C_Certifying Engine Families
 
Sec.  1048.245  How do I demonstrate that my engine family complies with
evaporative emission standards?

    (a) For certification, your engine family is considered in 
compliance with the evaporative emission standards in subpart B of this 
part if you do either of the following:
    (1) You have test results showing that evaporative emissions in the 
family are at or below the standards throughout the useful life.
    (2) Where applicable, you comply with the design specifications in 
paragraph (e) of this section.
    (b) Your engine family does not comply if any fuel system 
representing that family has test results showing emission levels above 
the standards.
    (c) Use good engineering judgment to develop a test plan to 
establish deterioration factors to show how much emissions increase at 
the end of useful life.
    (d) If you adjust the emission levels for deterioration, round them 
to the same number of decimal places as the emission standard. Compare 
the rounded emission levels to the emission standard for each test fuel 
system.
    (e) You may demonstrate that your engine family complies with the 
evaporative emission standards by demonstrating that you use the 
following control technologies:
    (1) For certification to the standards specified in Sec.  
1048.105(a)(1), with the following technologies:
    (i) Use a tethered or self-closing gas cap on a fuel tank that stays 
sealed up to a positive pressure of 24.5 kPa (3.5 psig) or a vacuum 
pressure of 0.7 kPa (0.1 psig).
    (ii) [Reserved]
    (2) For certification to the standards specified in Sec.  
1048.105(a)(3), demonstrating that you use design features to prevent 
fuel boiling under all normal operation. You may do this using fuel 
temperature data measured during normal operation.
    (3) We may establish additional options for design-based 
certification where we find that new test data demonstrate that a 
technology will ensure compliance with the emission standards in this 
section.

[67 FR 68347, Nov. 8, 2002, as amended at 70 FR 40474, July 13, 2005]