40 CFR §205.51

1. (a)As used in this subpart, all terms not defined herein shall have the meaning given them in the Act or in other subparts of this part.
   1. (1)Acceptable Quality Level means the maximum percentage of failing vehicles that for purposes of sampling inspection, can be considered satisfactory as a process average.
   2. (2)Acceptance of a batch means that the number of noncomplying vehicles in the batch sample is less than or equal to the acceptance number as determined by the appropriate sampling plan.
   3. (3)Batch means the collection of vehicles of the same category, configuration or subgroup thereof as designated by the Administrator in a test request, from which a batch sample is to be drawn, and inspected to determine conformance with the acceptability criteria.
   4. (4)Batch size means the number as designated by the Administrator in the test request of vehicles of the same category or configuration in a batch.
   5. (5)Batch sample means the collection of vehicles of the same category, configuration or subgroup thereof which are drawn from a batch and from which test samples are drawn.
   6. (6)Batch sample size means the number of vehicles of the same category or configuration in a batch sample.
   7. (7)Cab over axle or cab over engine means the cab which contains the operator/passenger compartment is directly above the engine and front axle and the entire cab can be tilted forward to permit access to the engine compartment.
   8. (8)Category means a group of vehicle configurations which are identical in all material aspects with respect to the parameters listed in § 205.55-2.
   9. (9)Configuration means the basic classification unit of a manufacturer's product line and is comprised of all vehicle designs, models or series which are identical in material aspects with respect to the parameters listed in § 205.55-3.
   10. (10)Acceptance of a Batch sequence means that the number of rejected batches in the sequence is less than or equal to the acceptance number as determined by the appropriate sampling plan.
   11. (11)Rejection of a Batch sequence means that the number of rejected batches in a sequence is equal to or greater than the rejection number as determined by the appropriate sampling plan.
   12. (12)Capable of Transportation of Property on a street or highway means that the vehicle:
       1. (i)Is self propelled and is capable of transporting any material or fixed apparatus, or is capable of drawing a trailer or semi-trailer;
       2. (ii)Is capable of maintaining a cruising speed of at least 25 mph over level, paved surface;
       3. (iii)Is equipped or can readily be equipped with features customarily associated with practical street or highway use, such features including but not being limited to: A reverse gear and a differential, fifth wheel, cargo platform or cargo enclosure, and
       4. (iv)Does not exhibit features which render its use on a street or highway impractical, or highly unlikely, such features including, but not being limited to, tracked road means, an inordinate size or features ordinarily associated with combat or tactical vehicles.
   13. (13)Exhaust System means the system comprised of a combination of components which provides for enclosed flow of exhaust gas from engine exhaust port to the atmosphere.
   14. (14)Gross Combination Weight Rating (GCWR) means the value specified by the manufacturer as the loaded weight of a combination vehicle.
   15. (15)Gross Vehicle Weight Rating (GVWR) means the value specified by the manufacturer as the loaded weight of a single vehicle.
   16. (16)Inspection Criteria means the rejection and acceptance numbers associated with a particular sampling plan.
   17. (17)Model year means the manufacturer's annual production period which includes January 1 of such calendar year: Provided, that if the manufacturer has no annual production period, the term “model year” shall mean the calendar year.
   18. (18)Noise Control System includes any vehicle part, component or system the primary purpose of which is to control or cause the reduction of noise emitted from a vehicle.
   19. (19)Noise emission test means a test conducted pursuant to the measurement methodology specified in this subpart.
   20. (20)[Reserved]
   21. (21)Rejection of a batch means the number of noncomplying vehicles in the batch sample is greater than or equal to the rejection number as determined by the appropriate sampling plan.
   22. (22)Shift means the regular production work period for one group of workers.
   23. (23)Test sample means the collection of vehicles from the same category, configuration or subgroup thereof which is drawn from the batch sample and which will receive noise emissions tests.
   24. (24)Failing vehicle means that the measured emissions of the vehicle, when measured in accordance with the applicable procedure, exceeds the applicable standard.
   25. (25)Acceptance of a vehicle means that the measured emissions of the vehicle when measured in accordance with the applicable procedure, conforms to the applicable standard.
   26. (26)Tampering means those acts prohibited by section 10(a)(2) of the Act.
   27. (27)Test sample size means the number of vehicles of the same category or configuration in a test sample.
   28. (28)Test vehicle means a vehicle selected and used to demonstrate compliance with the applicable noise emission standards.
   29. (29)Vehicle means any motor vehicle, machine or tractor, which is propelled by mechanical power and capable of transportation of property on a street or highway and which has a gross vehicle weight rating in excess of 10,000 pounds and a partially or fully enclosed operator's compartment.