Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:13:p28
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 13 (pt 28/56)
Character Range: 374473–377464

1 % max             0.99 - 1.01  ≤  1 % max      ≥  0.998
Pressures                 ≤  1 % max             0.99 - 1.01  ≤  1 % max      ≥  0.998
PM balance                ≤  1 % max             0.99 - 1.01  ≤  1 % max      ≥  0.998

9.2.1. Linearity verification
              9.2.1.1. Introduction

              A linearity verification shall be performed for each measurement system listed in Table 7. At least 10 reference values, or as specified otherwise, shall be introduced to the measurement system. For stand-alone pressure and temperature linearity verifications, at least three reference values shall be selected. The measured values shall be compared to the reference values by using a least squares linear regression in accordance with equation 11 in paragraph 7.8.7. The maximum limits in Table 7 refer to the maximum values expected during testing.

9.2.1.2. General requirements
 The measurement systems shall be warmed up according to the recommendations of the instrument manufacturer. The measurement systems shall be operated at their specified temperatures, pressures and flows.
       9.2.1.3. Procedure
 The linearity verification shall be run for each normally used operating range with the following steps:
(a) The instrument shall be set at zero by introducing a zero signal. For gas analyzers, purified synthetic air (or nitrogen) shall be introduced directly to the analyzer port;
(b) The instrument shall be spanned by introducing a span signal. For gas analyzers, an appropriate span gas shall be introduced directly to the analyzer port;
(c) The zero procedure of (a) shall be repeated;
(d) The verification shall be established by introducing at least 10 reference values (including zero) that are within the range from zero to the highest values expected during emission testing. For gas analyzers, known gas concentrations in accordance with paragraph 9.3.3.2. shall be introduced directly to the analyzer port;
(e) At a recording frequency of at least 1 Hz, the reference values shall be measured and the measured values recorded for 30 seconds;
(f) The arithmetic mean values over the 30 seconds period shall be used to calculate the least squares linear regression parameters according to equation 11 in paragraph 7.8.7;
(g) The linear regression parameters shall meet the requirements of paragraph 9.2., Table 7;
(h) The zero setting shall be rechecked and the verification procedure repeated, if necessary.
9.3. Gaseous emissions measurement and sampling system
9.3.1. Analyzer specifications
9.3.1.1. General
 The analyzers shall have a measuring range and response time appropriate for the accuracy required to measure the concentrations of the exhaust gas components under transient and steady state conditions.
 The electromagnetic compatibility (EMC) of the equipment shall be on a level as to minimize additional errors.
9.3.1.2. Accuracy
 The accuracy, defined as the deviation of the analyzer reading from the reference value, shall not exceed