40 CFR 1039.510
§ 1039.510 Which duty cycles do I use for transient testing?
United States · 40 CFR — Protection of Environment · Status: effective
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- Citation
- 40 CFR 1039.510, § 1039.510 Which duty cycles do I use for transient testing?, United States, version 1 as recorded 2026-07-09, yourstate.us, https://yourstate.us/provision/195113
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Full text
(a) Measure emissions by testing the engine on a dynamometer with one of the following transient duty cycles to determine whether it meets the transient emission standards in § 1039.101(a):
(1) For variable-speed engines, use the transient duty cycle described in appendix VI of this part.
(2) [Reserved]
(b) The transient test sequence consists of an initial run through the transient duty cycle from a cold start, 20 minutes with no engine operation, then a final run through the same transient duty cycle. Calculate the official transient emission result from the following equation:
Legislative history
This is a federal regulation, adopted through agency rulemaking under the Administrative Procedure Act — not enacted by a recorded vote of Congress.