Operations after test Clause Samples
Operations after test. At the completion of the test, the measurement of the diluted exhaust gas volume, the gas flow into the collecting bags and the particulate sample pump must be stopped. For an integrating analyser system, sampling must continue until system response times have elapsed. The concentrations of the collecting bags, if used, must be analysed as soon as possible and in any case not later than 20 minutes after the end of the test cycle. After the emission test, a zero gas and the same span gas must be used for re-checking the analysers. The test will be considered acceptable if the difference between the pre-test and post-test results is less than 2 per cent of the span gas value. For diesel engines only, the particulate filters must be returned to the weighing chamber no later than one hour after completion of the test and must be conditioned in a closed, but unsealed petri dish for at least one hour, but not more than 80 hours before weighing.
Operations after test. At the completion of the test, the measurement of the exhaust gas mass flow rate, the diluted exhaust gas volume, the gas flow into the collecting bags and the particulate sample pump shall be stopped. For an integrating analyser system, sampling shall continue until system response times have elapsed. The concentrations of the collecting bags, if used, shall be analysed as soon as possible and in any case not later than 20 minutes after the end of the test cycle. After the emission test, a zero gas and the same span gas shall be used for re- checking the analysers. The test will be considered acceptable if the difference between the pre-test and post-test results is less than 2 per cent of the span gas value. The particulate filter shall be returned to the weighing chamber no later than one hour after completion of the test. It shall be conditioned in a petri dish, which is protected against dust contamination and allows air exchange, for at least one hour, and then weighed. The gross weight of the filter shall be recorded.