[Code of Federal Regulations]
[Title 40, Volume 30]
[Revised as of July 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR1048.315]

[Page 563-564]
 
                   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 D_Testing Production-line Engines
 
Sec. 1048.315  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 this criteria on an engine-family 
basis. See Sec. 1048.320 for the requirements that apply to individual 
engines that fail a production-line test.

[[Page 564]]

    (a) Calculate your test results. Round them to the number of decimal 
places in the emission standard expressed to one more decimal place.
    (1) Initial and final test results. Calculate and round the test 
results for each engine. If you do several tests on an 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 engine.
    (2) Final deteriorated test results. Apply the deterioration factor 
for the engine family to the final test results (see Sec. 1048.240(c)).
    (b) Construct the following CumSum Equation for each engine family 
(for HC+NOX and for CO emissions): 
[GRAPHIC] [TIFF OMITTED] TR08NO02.006

Where:

Ci = The current CumSum statistic.
Ci-1 = The previous CumSum statistic. For the first test, 
CumSum statistic is 0 (i.e. C1 = 0).
Xi = The current emission test result for an individual 
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. 
1048.315(a)).
    (d) After each new test, recalculate the CumSum statistic.
    (e) If you test more than the required number of 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.
    (h) If you amend the application for certification for an engine 
family (see Sec. 1048.225), do not change any previous calculations of 
sample size or CumSum statistics for the model year.