§ 1051.310 How must I select vehicles or engines for production-line testing?
(a) Test engines from each engine family as described in this section based on test periods, as follows:
(1) For engine families with projected U.S.-directed production volume of at least 1,600, the test periods are defined as follows:
(i) If your annual production period is 120 days or less, the whole model year constitutes a single test period.
(ii) If your annual production period is 121 to 210 days, divide the annual production period evenly into two test periods.
(iii) If your annual production period is 211 to 300 days, divide the annual production period evenly into three test periods.
(iv) If your annual production period is 301 days or longer, divide the annual production period evenly into four test periods. For example, if your annual production period is 392 days (56 weeks), divide the annual production period into four test periods of 98 days (14 weeks).
(2) For engine families with projected U.S.-directed production volume below 1,600, the whole model year constitutes a single test period.
(b) Early in each test period, randomly select and test an engine from the end of the assembly line for each engine family.
(1) In the first test period for newly certified engines, randomly select and test one more engine. Then, calculate the required sample size for the model year as described in paragraph (c) of this section.