part_subject: "CONTROL OF EMISSIONS FROM NEW AND IN-USE NONROAD COMPRESSION-IGNITION ENGINES"
subpart_code: "D"
subpart_subject: "Emission Test Equipment Provisions"
section_number: "89.331"
section_subject: "Test conditions."
cfr_reference: "40 CFR 89.331"
title_name: "Title 40"
title_subject: "Protection of Environment"
parts_covered: "Parts 87 to 95"
revised_date: "Revised as of July 1, 2017"
publication_date: "As of July 1, 2017"
contains_description: "Containing a codification of documents of general applicability and future effect"
publication_info: "Published by the Office of the Federal Register National Archives and Records Administration as a Special Edition of the Federal Register"
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(a)General requirements. Calculate all volumes and volumetric flow rates at standard conditions for temperature and pressure (0 °C and 101.3 kPa), and these conditions must be used consistently throughout all calculations.
(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 p and expressed in kPa), and determine the parameter f according to the following provisions:
(1)Naturally aspirated and mechanically supercharged engines:
(2)Turbocharged engine with or without cooling of inlet air:
(c)For a test to be recognized as valid, the parameter f shall be between the limits as shown below: