CFR > Title 40 - Protection of Environment > CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY > SUBCHAPTER U—AIR POLLUTION CONTROLS (Parts 1027–1074) > PART 1065—ENGINE-TESTING PROCEDURES > SUBPART H—Engine Fluids, Test Fuels, Analytical Gases and Other Calibration Standards (§1065.701 to §1065.790) > 1065.790—Mass standards.

1065.790—Mass standards.

(a) PM balance calibration weights. Use PM balance calibration weights that are certified as NIST-traceable within 0.1 % uncertainty. Calibration weights may be certified by any calibration lab that maintains NIST-traceability. Make sure your lowest calibration weight has no greater than ten times the mass of an unused PM-sample medium.
(b) Dynamometer calibration weights. [Reserved]