[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: 40CFR1051.315]

[Page 643]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 1051_CONTROL OF EMISSIONS FROM RECREATIONAL ENGINES
AND VEHICLES--Table of Contents
 
         Subpart D_Testing Production-Line Vehicles and Engines
 
Sec.  1051.315  How do I know when my engine family fails the production-line
testing requirements?

    This section describes the pass-fail criteria for the production-
line testing requirements. We apply these criteria on an engine family 
basis. SeeSec.  1051.320 for the requirements that apply to individual 
vehicles or engines that fail a production-line test.
    (1) Initial and final test results. Calculate and round the test 
results for each vehicle or engine. If you do several tests on a vehicle 
or engine, calculate the initial test results, then add them together 
and divide by the number of tests and round for the final test results 
on that vehicle or engine.
    (2) Final deteriorated test results. Apply the deterioration factor 
for the engine family to the final test results (see Sec.  1051.240(c)).
    (b) Construct the following CumSum Equation for each engine family 
for HC, NOX (or HC+NOX), and CO emissions (and 
other regulated pollutants):
[GRAPHIC] [TIFF OMITTED] TR08NO02.010

Where:

Ci = The current CumSum statistic.
Ci-1 = The previous CumSum statistic. For the first test, the 
CumSum statistic is 0 (i.e. C1 = 0).
Xi = The current emission test result for an individual 
vehicle or engine.
STD = Emission standard.

    (c) Use final deteriorated test results to calculate the variables 
in the equation in paragraph (b) of this section (see Sec.  
1051.315(a)).
    (d) After each new test, recalculate the CumSum statistic.
    (e) If you test more than the required number of vehicles or 
engines, include the results from these additional tests in the CumSum 
Equation.
    (f) After each test, compare the current CumSum statistic, 
Ci, to the recalculated Action Limit, H, defined as H = 5.0 x 
[sigma].
    (g) If the CumSum statistic exceeds the Action Limit in two 
consecutive tests, the engine family fails the production-line testing 
requirements of this subpart. Tell us within ten working days if this 
happens. You may request to amend the application for certification to 
raise the FEL of the engine family at this point if you meet the 
requirements of Sec.  1051.225(f).
    (h) If you amend the application for certification for an engine 
family under Sec.  1051.225, do not change any previous calculations of 
sample size or CumSum statistics for the model year.

[67 FR 68347, Nov. 8, 2002, as amended at 70 FR 40499, July 13, 2005]