2009-05-19_REVISION - M1978039HR (28)

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• • • Environmental Protection Agency plume as it emerges from the emission out- let, opacity observations shall be made be- yond the point in the plume at which con- densed water vapor is no longer visible. The observer shall record the approximate dis- tance from the emission outlet to the point in the plume at which the observations are made. 2.3.2 Detached Steam Plume. When water vapor in the plume condenses and becomes visible at a distinct distance from the emis- sion outlet, the opacity of emissions should be evaluated at the emission outlet prior to the condensation of water vapor and the for- mation of the steam plume. 2.4 Recording Observations. Opacity obser- vations shall be recorded to the nearest 5 percent at 15-second intervals on an observa- tional record sheet. (See Figure 9-2 for an ex- ample.) A minimum of 24 observations shall be recorded. Each momentary observation recorded shall be deemed to represent the av- erage opacity of emissions for a 15-second pe- riod. 2.5 Data Reduction. Opacity shall be deter- mined as an average of 24 consecutive obser- vations recorded at 15-second intervals. Di- vide the observations recorded on the record sheet into sets of 24 consecutive observa- tions. A set is composed of any 24 consecu- tive observations. Sets need not be consecu- tive in time and in no case shall two sets overlap. For each set of 24 observations, cal- culate the average by summing the opacity of the 24 observations and dividing this sum by 24. If an applicable standard specifies an averaging time requiring more than 24 obser- vations, calculate the average for all obser- vations made during the specified time pe- riod. Record the average opacity on a record sheet. (See Figure 9-1 for an example.) 3. Qualifications and Testing 3.1 Certification Requirements. To receive certification as a qualified observer, a can- didate must be tested and demonstrate the ability to assign opacity readings in 5 per- cent increments to 25 different black plumes and 25 different white plumes, with an error not to exceed 15 percent opacity on any one reading and an average error not to exceed 7.5 percent opacity in each category. Can- didates shall be tested according to the pro- cedures described in section 3.2. Smoke gen- erators used pursuant to section 3.2 shall be equipped with a smoke meter which meets the requirements of section 3.3. The certification shall be valid for a period of 6 months, at which time the qualification procedure must be repeated by any observer in order to retain certification. 3.2 Certification Procedure. The certifi- cation test consists of showing the candidate a complete run of 50 plumes-25 black plumes and 25 white plumes-generated by a smoke generator. Plumes within each set of 25 black and 25 white runs shall be presented in Pt. 60, App. A-4, Meth. 9 random order. The candidate assigns an opacity value to each plume and records his observation on a suitable form. At the com- pletion of each run of 50 readings, the score of the candidate is determined. If a can- didate fails to qualify, the complete run of 50 readings must be repeated in any retest. The smoke test may be administered as part of a smoke school or training program, and may be preceded by training or familiarization runs of the smoke generator during which candidates are shown black and white plumes of known opacity. 3.3 Smoke Generator Specifications. Any smoke generator used for the purposes of section 3.2 shall be equipped with a smoke meter installed to measure opacity across the diameter of the smoke generator stack. The smoke meter output shall display instack opacity based upon a pathlength equal to the stack exit diameter, on a full 0 to 100 percent chart recorder scale. The smoke meter optical design and performance shall meet the specifications shown in Table 9-1. The smoke meter shall be calibrated as prescribed in section 3.3.1 prior to the con- duct of each smoke reading test. At the com- pletion of each test, the zero and span drift shall be checked and if the drift exceeds ±1 percent opacity, the condition shall be cor- rected prior to conducting any subsequent test runs. The smoke meter shall be dem- onstrated, at the time of installation, to meet the specifications listed in Table 9-1. This demonstration shall be repeated fol- lowing any subsequent repair or replacement of the photocell or associated electronic cir- cuitry including the chart recorder or output meter, or every 6 months, whichever occurs first. TABLE 9-1-SMOKE METER DESIGN AND PERFORMANCE SPECIFICATIONS Parameter I Specification a. Light source ................ Incandescent lamp operated at nominal rated voltage. b. Spectral response of Photopic (daylight spectral re- photocell. sponse of the human eye--Ci- tation 3). c. Angle of view .............. 15° maximum total angle. d. Angle of projection ...... 15° maximum total angle. e. Calibration error .......... t3% opacity, maximum. f. Zero and span drift ...... ±1 % opacity, 30 minutes. g. Response time ............ 5 seconds. 3.3.1 Calibration. The smoke meter is cali- brated after allowing a minimum of 30 min- utes warmup by alternately producing simu- lated opacity of 0 percent and 100 percent. When stable response at 0 percent or 100 per- cent is noted, the smoke meter is adjusted to produce an output of 0 percent or 100 per- cent, as appropriate. This calibration shall be repeated until stable 0 percent and 100 313