40 CFR 90.209 - Maintenance of records.
(1) EPA engine family identification code;
(4) Projected production volume for the model year; and
(1) The engine family;
(2) The actual applicable production volume;
(3) The values required to calculate credits as given in § 90.207;
(4) The resulting type and number of credits generated/required;
(5) How and where credit surpluses are dispersed; and
(6) How and through what means credit deficits are met.
(c) The manufacturer must retain all records required to be maintained under this section for a period of eight years from the due date for the end-of-model year report. Records may be retained as hard copy or reduced to microfilm, ADP diskettes, and so forth, depending on the manufacturer's record retention procedure; provided, that in every case all information contained in the hard copy is retained.
(d) Nothing in this section limits the Administrator's discretion in requiring the manufacturer to retain additional records, or submit information not specifically required by this section, if otherwise permitted by law.
(f) EPA may, pursuant to § 90.123, void ab initio a certificate of conformity for an engine family for which the manufacturer fails to retain the records required in this section or to provide such information to the Administrator upon request.