[Code of Federal Regulations]
[Title 40, Volume 31]
[Revised as of July 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR1065.315]

[Page 721]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 1065_ENGINE-TESTING PROCEDURES--Table of Contents
 
                Subpart D_Calibrations and Verifications
 
Sec.  1065.315  Pressure, temperature, and dewpoint calibration.

    (a) Calibrate instruments for measuring pressure, temperature, and 
dewpoint upon initial installation. Follow the instrument manufacturer's 
instructions and use good engineering judgment to repeat the 
calibration, as follows:
    (1) Pressure. We recommend temperature-compensated, digital-
pneumatic, or deadweight pressure calibrators, with data-logging 
capabilities to minimize transcription errors. We recommend using 
calibration reference quantities that are NIST-traceable within 0.5% 
uncertainty.
    (2) Temperature. We recommend digital dry-block or stirred-liquid 
temperature calibrators, with datalogging capabilities to minimize 
transcription errors. We recommend using calibration reference 
quantities that are NIST-traceable within 0.5% uncertainty.
    (3) Dewpoint. We recommend a minimum of three different temperature-
equilibrated and temperature-monitored calibration salt solutions in 
containers that seal completely around the dewpoint sensor. We recommend 
using calibration reference quantities that are NIST-traceable within 
0.5% uncertainty.
    (b) You may remove system components for off-site calibration. We 
recommend specifying calibration reference quantities that are NIST-
traceable within 0.5% uncertainty.

                        Flow-Related Measurements