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Code of Federal Regulations (Last Updated: July 5, 2024) |
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Title 40 - Protection of Environment |
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Chapter I - Environmental Protection Agency |
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SubChapter C - Air Programs |
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Part 91 - Control of Emissions from Marine Spark-Ignition Engines |
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Subpart D - Emission Test Equipment Provisions |
§ 91.311 - Test conditions.
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§ 91.311 Test conditions.
(a) General requirements.
(1) Ambient temperature levels encountered by the test engine throughout the test sequence may not be less than 20 °C nor more than 30 °C.
(2) Calculate all volumes and volumetric flow rates at standard conditions for temperature and pressure. Use these conditions consistently throughout all calculations. Standard conditions for temperature and pressure are 25 °C and 101.3 kPa.
(b) Engine test conditions. Measure the absolute temperature (designated as T and expressed in Kelvin) of the engine air at the inlet to the engine and the dry atmospheric pressure (designated as ps and expressed in kPa. Determine the parameter f according to the following provisions:
(3) For a test to be recognized as valid, the parameter f must be between the limits as shown below: