CFR > Title 40 - Protection of Environment > CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY > SUBCHAPTER C—AIR PROGRAMS (Parts 50–99) > PART 89—CONTROL OF EMISSIONS FROM NEW AND IN-USE NONROAD COMPRESSION-IGNITION ENGINES > SUBPART E—Exhaust Emission Test Procedures (§89.401 to §89.425) > 89.416—Raw exhaust gas flow.

89.416—Raw exhaust gas flow.

The exhaust gas flow shall be determined by one of the methods described in this section and conform to the tolerances of table 3 in appendix A to subpart D:
(a) Measurement of the air flow and the fuel flow by suitable metering systems (for details see SAE J244. This procedure has been incorporated by reference. See § 89.6.) and calculation of the exhaust gas flow as follows:

Code of Federal Regulations

GEXHW = GAIRW GFUEL(for wet exhaust mass)
or

Code of Federal Regulations

VEXHD = VAIRD (−.767) × GFUEL(for dry exhaust volume)
or

Code of Federal Regulations

VEXHW = VAIRW .749 × GFUEL(for wet exhaust volume)
(b) Exhaust mass calculation from fuel consumption (see § 89.415) and exhaust gas concentrations using the method found in § 89.418.

Code of Federal Regulations

[59 FR 31335, June 17, 1994. Redesignated at 63 FR 56996, Oct. 23, 1998]