[Code of Federal Regulations] [Title 40, Volume 18] [Revised as of July 1, 2003] From the U.S. Government Printing Office via GPO Access [CITE: 40CFR92.105] [Page 423-424] TITLE 40--PROTECTION OF ENVIRONMENT CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PART 92--CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES-- Table of Contents Subpart B--Test Procedures Sec. 92.105 General equipment specifications. (a) Chart recorders. (1) The recommended minimum chart speed for gaseous measurements is 1 cm per minute. (Higher chart speeds are required for smoke measurements during the acceleration phases of the test sequence.) (2) All chart recorders (analyzers, torque, rpm, etc.) shall be provided with automatic markers which indicate ten second intervals. Preprinted chart paper (ten second intervals) may be used in lieu of the automatic markers provided the correct chart speed is used. (Markers which indicate 1 second intervals are required for smoke measurements during the acceleration phases of the test sequence.) (b) Automatic data collection. (1) In lieu of the use of chart recorders, automatic data collection equipment may be used to record all required data. The automatic data collection equipment must be capable of sampling at least two records per second. (2) Other means may be used provided they produce a permanent visual data record of a quality equal to or better than those required by this subpart (e.g., tabulated data, traces, or plots). (c) Temperature measurements. (1) The following temperature measurements shall be accurate to within 1.0 deg.F (0.6 deg.C): (i) Temperature measurements used in calculating the engine intake humidity; (ii) The temperature of the fuel, in volume measuring flow rate devices; (iii) The temperature of the sample within the water trap(s); (iv) Temperature measurements used to correct gas volumes (e.g., to standard conditions) or to calculate mass or moles of a sample. (2) All other temperature measurements shall be accurate within 3.0 deg.F (1.7 deg.C). (d) Electrical measurements. (1) Voltmeters shall have accuracy and precision of 1 percent of point or better. (2) Ammeters shall have accuracy and precision of 1 percent of point or better. (3) Wattmeters shall have accuracy and precision of 1 percent of point or better. (4) Instruments used in combination to measure engine power output shall comply with the requirements of Sec. 92.106. (e) Pressure measurements. (1) Gauges and transducers used to measure any pressures used to correct gas volumes [[Page 424]] (e.g., to standard conditions) or to calculate mass or moles of a sample shall have an accuracy and precision of 0.1 percent of absolute pressure at point or better. (2) Gauges and transducers used to measure any other pressures shall have an accuracy and precision of 1 percent of absolute pressure at point or better.