[Code of Federal Regulations]

[Title 40, Volume 31]

[Revised as of July 1, 2006]

From the U.S. Government Printing Office via GPO Access

[CITE: 40CFR1065.215]



[Page 704]

 

                   TITLE 40--PROTECTION OF ENVIRONMENT

 

         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)

 

PART 1065_ENGINE-TESTING PROCEDURES--Table of Contents

 

                    Subpart C_Measurement Instruments

 

Sec.  1065.215  Pressure transducers, temperature sensors, and dewpoint 

sensors.



    (a) Application. Use instruments as specified in this section to 

measure pressure, temperature, and dewpoint.

    (b) Component requirements. We recommend that you use pressure 

transducers, temperature sensors, and dewpoint sensors that meet the 

specifications in Table 1 of Sec.  1065.205. Note that your overall 

systems for measuring pressure, temperature, and dewpoint must meet the 

calibration and verifications in Sec.  1065.315.

    (c) Temperature. For PM-balance environments or other precision 

temperature measurements over a narrow temperature range, we recommend 

thermistors. For other applications we recommend thermocouples that are 

not grounded to the thermocouple sheath. You may use other temperature 

sensors, such as resistive temperature detectors (RTDs).

    (d) Pressure. Pressure transducers must be located in a temperature-

controlled environment, or they must compensate for temperature changes 

over their expected operating range. Transducer materials must be 

compatible with the fluid being measured. For atmospheric pressure or 

other precision pressure measurements, we recommend either capacitance-

type, quartz crystal, or laser-interferometer transducers. For other 

applications, we recommend either strain gage or capacitance-type 

pressure transducers. You may use other pressure-measurement 

instruments, such as manometers, where appropriate.

    (e) Dewpoint. For PM-stabilization environments, we recommend 

chilled-surface hygrometers. For other applications, we recommend thin-

film capacitance sensors. You may use other dewpoint sensors, such as a 

wet-bulb/dry-bulb psychrometer, where appropriate.



                        Flow-Related Measurements