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e-CFR data is current as of November 25, 2020

Title 40Chapter ISubchapter UPart 1066Subpart A → §1066.5

Title 40: Protection of Environment
Subpart A—Applicability and General Provisions

§1066.5   Overview of this part 1066 and its relationship to the standard-setting part.

(a) This part specifies procedures that can apply generally to testing various categories of vehicles. See the standard-setting part for directions in applying specific provisions in this part for a particular type of vehicle. Before using this part's procedures, read the standard-setting part to answer at least the following questions:

(1) What drive schedules must I use for testing?

(2) Should I warm up the test vehicle before measuring emissions, or do I need to measure cold-start emissions during a warm-up segment of the duty cycle?

(3) Which exhaust constituents do I need to measure? Measure all exhaust constituents that are subject to emission standards, any other exhaust constituents needed for calculating emission rates, and any additional exhaust constituents as specified in the standard-setting part. See 40 CFR 1065.5 regarding requests to omit measurement of N2O and CH4 for vehicles not subject to an N2O or CH4 emission standard.

(4) Do any unique specifications apply for test fuels?

(5) What maintenance steps may I take before or between tests on an emission-data vehicle?

(6) Do any unique requirements apply to stabilizing emission levels on a new vehicle?

(7) Do any unique requirements apply to test limits, such as ambient temperatures or pressures?

(8) What requirements apply for evaporative and refueling emissions?

(9) Are there any emission standards specified at particular operating conditions or ambient conditions?

(10) Do any unique requirements apply for durability testing?

(b) The testing specifications in the standard-setting part may differ from the specifications in this part. In cases where it is not possible to comply with both the standard-setting part and this part, you must comply with the specifications in the standard-setting part. The standard-setting part may also allow you to deviate from the procedures of this part for other reasons.

(c) The following table shows how this part divides testing specifications into subparts:

Table 1 of §1066.5—Description of Part 1066 Subparts

This subpartDescribes these specifications or procedures
Subpart AApplicability and general provisions.
Subpart BEquipment for testing.
Subpart CDynamometer specifications.
Subpart DCoastdowns for testing.
Subpart EHow to prepare your vehicle and run an emission test.
Subpart FHow to test electric vehicles and hybrid electric vehicles.
Subpart GTest procedure calculations.
Subpart HCold temperature testing.
Subpart IExhaust emission test procedures for motor vehicles.
Subpart JEvaporative and refueling emission test procedures.
Subpart KDefinitions and reference material.

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