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40 CFR Table B-1 to Subpart B of Part 53: Table B-1 to Subpart B of Part 53—Performance Limit Specifications for Automated Methods

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  1. Title 40—Protection of Environment
  2. CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY
  3. SUBCHAPTER C—AIR PROGRAMS
  4. PART 53—AMBIENT AIR MONITORING REFERENCE AND EQUIVALENT METHODS
  5. Subpart B—Procedures for Testing Performance Characteristics of Automated Methods for SO2, CO, O3, and NO2

Performance parameter Units 1 SO2 O3 CO NO2 (Std. range) Definitions and test procedures

Std. range 3 Lower range 2 3 Std. range 3 Lower range 2 3 Std. range 3 Lower range 2 3

1. Range ppm 0-0.5 <0.5 0-0.5 <0.5 0-50 <50 0-0.5 Sec. 53.23(a)

2. Noise ppm 0.001 0.0005 0.0025 0.001 0.2 0.1 0.005 Sec. 53.23(b)

3. Lower detectable limit ppm 0.002 0.001 0.005 0.002 0.4 0.2 0.010 Sec. 53.23(c)

4. Interference equivalent

Each interferent ppm ±0.005 4 ±0.005 ±0.005 ±0.005 ±1.0 ±0.5 ±0.02 Sec. 53.23(d)

Total, all interferents ppm - - - - - - 0.04 Sec. 53.23(d)

5. Zero drift, 12 and 24 hour ppm ±0.004 ±0.002 ±0.004 ±0.002 ±0.5 ±0.3 ±0.02 Sec. 53.23(e)

6. Span drift, 24 hour

20% of upper range limit Percent - - - - - - ±20.0 Sec. 53.23(e)

80% of upper range limit Percent ±3.0 ±3.0 ±3.0 ±3.0 ±2.0 ±2.0 ±5.0 Sec. 53.23(e)

7. Lag time Minutes 2 2 2 2 2.0 2.0 20 Sec. 53.23(e)

8. Rise time Minutes 2 2 2 2 2.0 2.0 15 Sec. 53.23(e)

9. Fall time Minutes 2 2 2 2 2.0 2.0 15 Sec. 53.23(e)

10. Precision

20% of upper range limit - - - - - - Sec. 53.23(e)

Percent 5 2 2 2 2 1.0 1.0 4 Sec. 53.23(e)

80% of upper range limit - - - - - - Sec. 53.23(e)

Percent 5 2 2 2 2 1.0 1.0 6 Sec. 53.23(e) Sec. 53.23(e)

1 To convert from parts per million (ppm) to µg/m3 at 25 °C and 760 mm Hg, multiply by M/0.02447, where M is the molecular weight of the gas. Percent means percent of the upper measurement range limit.

2 Tests for interference equivalent and lag time do not need to be repeated for any lower range provided the test for the standard range shows that the lower range specification (if applicable) is met for each of these test parameters.

3 For candidate analyzers having automatic or adaptive time constants or smoothing filters, describe their functional nature, and describe and conduct suitable tests to demonstrate their function aspects and verify that performances for calibration, noise, lag, rise, fall times, and precision are within specifications under all applicable conditions. For candidate analyzers with operator-selectable time constants or smoothing filters, conduct calibration, noise, lag, rise, fall times, and precision tests at the highest and lowest settings that are to be included in the FRM or FEM designation.

4 For nitric oxide interference for the SO2 ultraviolet fluorescence (UVF) method, interference equivalent is ±0.003 ppm for the lower range.

5 Standard deviation expressed as percent of the URL.

Collected 2026-08-27T02:26:04Z. Source file · JSON

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