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Title 40

Displaying title 40, up to date as of 7/09/2026. Title 40 was last amended 7/09/2026.
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Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter UAir Pollution Controls1000 – 1099
Part 1065Engine-Testing Procedures1065.1 – 1065.1145
Subpart CMeasurement Instruments1065.201 – 1065.298
§ 1065.201Overview and general provisions.
§ 1065.202Data updating, recording, and control.
§ 1065.205Performance specifications for measurement instruments.
Measurement of Engine Parameters and Ambient Conditions1065.210 – 1065.215
§ 1065.210Work input and output sensors.
§ 1065.215Pressure transducers, temperature sensors, and dewpoint sensors.
Flow-Related Measurements1065.220 – 1065.248
§ 1065.220Fuel flow meter.
§ 1065.225Intake-air flow meter.
§ 1065.230Raw exhaust flow meter.
§ 1065.240Dilution air and diluted exhaust flow meters.
§ 1065.245Sample flow meter for batch sampling.
§ 1065.247Diesel exhaust fluid flow rate.
§ 1065.248Gas divider.
Co and C02 Measurements
Hydrocarbon, H2, and H2O Measurements1065.250 – 1065.257
§ 1065.250Nondispersive infrared analyzer.
§ 1065.255H2 measurement devices.
§ 1065.257H2O measurement devices.
Hydrocarbon Measurements1065.260 – 1065.269
§ 1065.260Flame-ionization detector.
§ 1065.265Nonmethane cutter.
§ 1065.266Fourier transform infrared analyzer.
§ 1065.267Gas chromatograph with a flame ionization detector.
§ 1065.269Photoacoustic analyzer for ethanol and methanol.
NOX, N2O, and NH3 Measurements1065.270 – 1065.277
§ 1065.270Chemiluminescent NOX analyzer.
§ 1065.272Nondispersive ultraviolet NOX analyzer.
§ 1065.274Zirconium dioxide (ZrO2) NOX analyzer.
§ 1065.275N2O measurement devices.
§ 1065.277NH3 measurement devices.
O2 And Air-to-Fuel Ratio Measurements1065.280 – 1065.284
§ 1065.280Paramagnetic and magnetopneumatic O2 detection analyzers.
§ 1065.284Zirconium dioxide (ZrO2) air-fuel ratio and O2 analyzer.
PM Measurements1065.290 – 1065.298
§ 1065.290PM gravimetric balance.
§ 1065.295PM inertial balance for field-testing analysis.
§ 1065.298Correcting real-time PM measurement based on gravimetric PM filter measurement for field-testing analysis.