subpart_subject: "Engine Fluids, Test Fuels, Analytical Gases and Other Calibration Standards"
section_number: "1065.715"
section_subject: "Natural gas."
cfr_reference: "40 CFR 1065.715"
title_name: "Title 40"
title_subject: "Protection of Environment"
parts_covered: "Part 1060 to End"
revised_date: "Revised as of July 1, 2019"
publication_date: "As of July 1, 2019"
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)Except as specified in paragraph (b) of this section, natural gas for testing must meet the specifications in the following table:
(b)In certain cases you may use test fuel not meeting the specifications in paragraph (a) of this section, as follows:
(1)You may use fuel that your in-use engines normally use, such as pipeline natural gas.
(2)You may use fuel meeting alternate specifications if the standard-setting part allows it.
(3)You may ask for approval to use fuel that does not meet the specifications in paragraph (a) of this section, but only if using the fuel would not adversely affect your ability to demonstrate compliance with the applicable standards.
(c)When we conduct testing using natural gas, we will use fuel that meets the specifications in paragraph (a) of this section.
(d)At ambient conditions, natural gas must have a distinctive odor detectable down to a concentration in air not more than one-fifth the lower flammable limit.