Document ID: chunk:federal_register_of_legislation:F2024L00447:reg:0:p16
Version: federal_register_of_legislation:F2024L00447
Segment Type: reg
Provision Reference: reg 0 (pt 16/57)
Character Range: 135651–138468

test, whichever is larger

NOX        ≤ 3 ppm per test              ≤ 2 % of reading or ≤ 3 ppm per test, whichever is larger

CH4        ≤ 10 ppm C1 per test          ≤ 2 % of reading or ≤ 10 ppm C1 per test, whichever is larger

THC        ≤ 10 ppm C1 per test          ≤ 2 % of reading or ≤ 10 ppm C1 per test, whichever is larger

If the difference between the pre-test and post-test results for the zero and span drift is higher than permitted, all test results shall be invalid and the test repeated.
              6.2. Checking the analyser for measuring particle emissions

              The zero level of the analyser shall be recorded in accordance with paragraph 4.6.

              6.3. Checking the on-road emission measurements

              The span gas concentration that was used for the calibration of the analysers in accordance with paragraph 4.5. at the test start shall cover at least 90 per cent of the concentration values obtained from 99 per cent of the measurements of the valid parts of the emissions test. It is permissible that 1 per cent of the total number of measurements used for evaluation exceeds the concentration of the span gas used by up to a factor of two. If these requirements are not met, the test shall be invalid.

              6.4. Consistency check of vehicle altitude

              In case altitude has only been measured with a GNSS, the GNSS altitude data shall be checked for consistency and, if necessary, corrected. The consistency of data shall be checked by comparing the latitude, longitude and altitude data obtained from the GNSS with the altitude indicated by a digital terrain model or a topographic map of suitable scale. Measurements that deviate by more than 40 m from the altitude depicted in the topographic map shall be manually corrected. The original and uncorrected data shall be retained and any corrected data shall be marked.

              The instantaneous altitude data shall be checked for completeness. Data gaps shall be completed by data interpolation. The correctness of interpolated data shall be verified by a topographic map. It is recommended to correct interpolated data if the following condition applies:

              The altitude correction shall be applied so that:

              where:

h(t)      —  vehicle altitude after the screening and principle check of data quality at data point t [m above sea level]

hGNSS(t)  —  vehicle altitude measured with GNSS at data point t [m above sea level]

hmap(t)   —  vehicle altitude based on topographic map at data point t [m above sea level]

6.5. Consistency check of GNSS vehicle speed
              The vehicle speed as determined by the GNSS shall be checked for consistency by calculating and comparing the total trip distance with reference measurements obtained from