40 CFR 1039.105
§ 1039.105 What smoke opacity standards must my engines meet?
United States · 40 CFR — Protection of Environment · Status: effective
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- Citation
- 40 CFR 1039.105, § 1039.105 What smoke opacity standards must my engines meet?, United States, version 1 as recorded 2026-07-09, yourstate.us, https://yourstate.us/provision/195086
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Full text
(a) The smoke opacity standards in this section apply to all engines subject to emission standards under this part, except for the following engines:
(1) Single-cylinder engines.
(2) Constant-speed engines.
(3) Engines certified to a PM emission standard or FEL of 0.07 g/kW-hr or lower.
(b) Measure smoke opacity as specified in § 1039.501(c). Smoke opacity from your engines may not exceed the following standards:
(1) 20 percent during the acceleration mode.
(2) 15 percent during the lugging mode.
(3) 50 percent during the peaks in either the acceleration or lugging modes.
Legislative history
This is a federal regulation, adopted through agency rulemaking under the Administrative Procedure Act — not enacted by a recorded vote of Congress.