Test Specifications for PM 10 , PM 2.5 and PM 10-2.5 Candidate Equivalent Methods

Specification PM 10 PM 2.5 PM 10-2.5 Class I Class II Class III Class II Class III Acceptable concentration range (R j ), µg/m 3 5-300 3-200 3-200 3-200 3-200 3-200. Minimum number of test sites 2 1 2 4 2 4. Minimum number of candidate method samplers or analyzers per site 3 3 3 1 3 1 3 1 3. 1 Number of reference method samplers per site 3 3 3 1 3 1 3 1 3. 1 Minimum number of acceptable sample sets per site for PM 10 methods: R j < 20 µg/m 3 3 R j > 20 µg/m 3 3 Total 10 Minimum number of acceptable sample sets per site for PM 2.5 and PM 10-2.5 candidate equivalent methods: R j < 15 µg/m 3 for 24-hr or R j < 8 µg/m 3 for 48-hr samples. 3 3 3 3 3. Rj > 15 µg/m 3 for 24-hr or R j > 8 µg/m 3 for 48-hr samples 3 3 3 3 3. Each season 10 23 23 23 23. Total, each site 10 23 23 (46 for two-season sites) 23 23 (46 for two-season sites). Precision of replicate reference method measurements, P Rj or RP Rj , respectively; RP for Class II or III PM 2.5 or PM 10-2.5 , maximum 5 µg/m 3 or 7%. 2 µg/m 3 or 5%. 10% 2 10% 2 10% 2 10%. 2 Precision of PM 2.5 or PM 10-2.5 candidate method, CP, each site 10% 2 15% 2 15% 2 15%. 2 Slope of regression relationship 1 ±0.10 1 ±0.05 1 ±0.10 1 ±0.10 1 ±0.10 1 ±0.12. Intercept of regression relationship, µg/m 3 0 ±5 0 ±1 Between: 13.55—(15.05 × slope), but not less than—1.5; and 16.56—(15.05 × slope), but not more than +1.5 Between: 15.05—(17.32 × slope), but not less than—2.0; and 15.05—(13.20 × slope), but not more than +2.0 Between: 62.05—(70.5 × slope), but not less than—3.5; and 78.95—(70.5 × slope), but not more than +3.5 Between: 70.50—(82.93 × slope), but not less than—7.0; and 70.50—(61.16 × slope), but not more than +7.0. Correlation of reference method and candidate method measurements ≥ 0.97 ≥ 0.97 ≥ 0.93—for CCV ≤ 0.4; ≥ 0.85 + 0.2 × CCV—for 0.4 ≤ CCV ≤ 0.5; ≥ 0.95—for CCV ≥ 0.5 1 Some missing daily measurement values may be permitted; see test procedure. 2 Calculated as the root mean square over all measurement sets. [89 FR 16386, Mar. 6, 2024]