7 Del. Admin. Code § app G § 1124-A-G-7.0
Current through Register Vol. 28, No. 3, September 1, 2024
Section 1124-A-G-7.0 - Pretest preparations7.1 Selection of sampling site.7.1.1 The location of the sampling site shall be determined from the applicable provisions of this regulation or purpose of the test (i.e., exhaust stack, inlet line, etc).7.1.2 The sample port shall be located at least 1.5 meters (4.9 feet) or two equivalent diameters upstream of the gas discharge to the atmosphere.7.2 Location of sample probe. The sample probe must be installed so that the probe is centrally located in the stack, pipe or duct and is sealed tightly at the stack port connection.7.3 Measurement systems preparation. Prior to the emission test, the measurement system must be assembled following the manufacturer's written instructions in preparing the sample interface and the organic analyzer. The system must be operable.7.4 Calibration error test. 7.4.1 Immediately prior to the test series (within two hours of the start of the test), zero gas and high-level calibration gas shall be introduced at the calibration valve assembly.7.4.2 The analyzer output shall be adjusted to the appropriate levels, if necessary.7.4.3 The predicted response for the low-level and mid-level gases shall be calculated based on a linear response line between the zero and high-level responses.7.4.4 Low-level and mid-level calibration gases shall be introduced successively to the measurement system.7.4.5 The analyzer responses for low-level and mid-level calibration gases shall be recorded, and the differences between the measurement system responses and the predicted responses shall be determined. These differences must be less than ±5% of the respective calibration gas value. If not, the measurement system shall be deemed not acceptable and must be replaced or repaired prior to testing. No adjustments to the measurement system shall be conducted after the calibration and before the drift determination found in 8.2 of this appendix.7.4.6 If adjustments are necessary before the completion of the test series, the drift checks shall be performed prior to the required adjustments, and the calibration following the adjustments shall be repeated.7.4.7 If multiple electronic ranges are to be used, each additional range must be checked with a mid-level calibration gas to verify the multiplication factor.7.5 Sampling System Bias Check 7.5.1 Perform the sampling system bias check by introducing calibration gases at the calibration valve installed at the outlet of the sampling probe. A zero gas and either the mid-range or high-range gas, whichever most closely approximates the effluent concentrations, shall be used for this check, as follows:7.5.2 Introduce the upscale calibration gas and record the gas concentration displayed by the analyzer on a form approved by the Department. Then introduce zero gas, and record the gas concentration displayed by the analyzer. During the sampling system bias check, operate the system at the normal sampling rate, and make no adjustments to the measurement system other than those necessary to achieve proper calibration gas flow rates at the analyzer. Alternately introduce the zero and upscale gases until a stable response is achieved. The tester shall determine the measurement system response time by observing the times required to achieve a stable response for both the zero and upscale gases. Note the longer of the two times as the response time.7.5.3 The sampling system bias check shall be considered invalid if the difference between the gas concentrations displayed by the measurement system for the analyzer calibration error check exceeds ±5% of the span for either the zero or upscale calibration gas. If an invalid calibration is exhibited, take corrective action, and repeat the sampling system bias check until acceptable performance is achieved. If adjustment to the analyzer is required, first repeat the analyzer calibration error check, then repeat the sampling system bias check.7.6 Response time test. 7.6.1 Zero gas shall be introduced into the measurement system at the calibration valve assembly.7.6.2 When the system output has stabilized, the owner or operator shall switch quickly to the high-level calibration gas.7.6.3 The time shall be recorded from the concentration change to the measurement system response equivalent to 95% of the step change.7.6.4 The test shall be repeated three times and the results averaged.7 Del. Admin. Code § app G § 1124-A-G-7.0