AQSQID: 250250042

Site Name: Boston - Roxbury

Location: Boston (Harrison Ave), MA

Reporting: True, Located: True

Current AQI: 38.0

Boston (Harrison Ave) MA, US: 42.329399, -71.082497

Date Observed (UTC) NOX NO NOY NO2 NO2Y SO2 OZONE CO PM10 PM2.5 AQI AQI/500
May 26, 2019, 11 p.m. 5.0 ppb (5) 0.0 ppb (0) 5.9 ppb (5) 5.0 ppb (5) N/A 0.0 ppb (0) 48.0 ppb (37) 0.17 ppb (2) N/A 9.0 μg/m3 (38) 38.0
 
May 26, 2019, 10 p.m. 4.0 ppb (4) 0.0 ppb (0) 5.1 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 51.0 ppb (39) 0.14 ppb (2) N/A 4.0 μg/m3 (17) 39.0
 
May 26, 2019, 9 p.m. 5.0 ppb (5) 1.0 ppb (1) 6.0 ppb (6) 4.0 ppb (4) N/A 0.0 ppb (0) 51.0 ppb (39) 0.13 ppb (1) N/A 5.0 μg/m3 (21) 39.0
 
May 26, 2019, 8 p.m. 2.0 ppb (2) 0.0 ppb (0) 3.2 ppb (3) 2.0 ppb (2) N/A 0.0 ppb (0) 51.0 ppb (39) 0.13 ppb (1) N/A 9.0 μg/m3 (38) 39.0
 
May 26, 2019, 7 p.m. 4.0 ppb (4) 1.0 ppb (1) 4.7 ppb (4) 3.0 ppb (3) N/A 0.0 ppb (0) 48.0 ppb (37) 0.16 ppb (2) N/A 8.0 μg/m3 (33) 37.0
 
May 26, 2019, 6 p.m. 2.0 ppb (2) 0.0 ppb (0) 3.0 ppb (3) 2.0 ppb (2) N/A 0.0 ppb (0) 48.0 ppb (37) 0.15 ppb (2) N/A 10.0 μg/m3 (42) 42.0
 
May 26, 2019, 5 p.m. 2.0 ppb (2) 0.0 ppb (0) 3.4 ppb (3) 2.0 ppb (2) N/A 0.0 ppb (0) 47.0 ppb (36) 0.16 ppb (2) N/A 8.0 μg/m3 (33) 36.0
 
May 26, 2019, 4 p.m. 3.0 ppb (3) 1.0 ppb (1) 3.5 ppb (3) 2.0 ppb (2) N/A 0.0 ppb (0) 45.0 ppb (35) 0.16 ppb (2) N/A 7.0 μg/m3 (29) 35.0
 
May 26, 2019, 3 p.m. 2.0 ppb (2) 0.0 ppb (0) 2.9 ppb (3) 2.0 ppb (2) N/A 0.0 ppb (0) 42.0 ppb (32) 0.15 ppb (2) N/A 5.0 μg/m3 (21) 32.0
 
May 26, 2019, 2 p.m. 4.0 ppb (4) 1.0 ppb (1) 4.7 ppb (4) 3.0 ppb (3) N/A 0.0 ppb (0) 37.0 ppb (28) 0.16 ppb (2) N/A 6.0 μg/m3 (25) 28.0
 
May 26, 2019, 1 p.m. 2.0 ppb (2) 0.0 ppb (0) 2.9 ppb (3) 2.0 ppb (2) N/A 0.0 ppb (0) 35.0 ppb (27) 0.15 ppb (2) N/A 11.0 μg/m3 (46) 46.0
 
May 26, 2019, noon 2.0 ppb (2) 1.0 ppb (1) 3.1 ppb (3) 2.0 ppb (2) N/A 0.0 ppb (0) 31.0 ppb (24) 0.14 ppb (2) N/A 9.0 μg/m3 (38) 38.0
 
May 26, 2019, 11 a.m. 2.0 ppb (2) 0.0 ppb (0) 3.1 ppb (3) 2.0 ppb (2) N/A 0.0 ppb (0) 30.0 ppb (23) 0.12 ppb (1) N/A 4.0 μg/m3 (17) 23.0
 
May 26, 2019, 10 a.m. 2.0 ppb (2) 0.0 ppb (0) 2.6 ppb (2) 2.0 ppb (2) N/A 0.0 ppb (0) 31.0 ppb (24) 0.12 ppb (1) N/A 4.0 μg/m3 (17) 24.0
 
May 26, 2019, 9 a.m. 2.0 ppb (2) 0.0 ppb (0) 2.0 ppb (2) 2.0 ppb (2) N/A 0.0 ppb (0) 30.0 ppb (23) 0.11 ppb (1) N/A 3.0 μg/m3 (12) 23.0
 
May 26, 2019, 8 a.m. 2.0 ppb (2) 0.0 ppb (0) 2.3 ppb (2) 2.0 ppb (2) N/A 0.0 ppb (0) 30.0 ppb (23) 0.11 ppb (1) N/A 3.0 μg/m3 (12) 23.0
 
May 26, 2019, 7 a.m. 2.0 ppb (2) 0.0 ppb (0) 2.3 ppb (2) 2.0 ppb (2) N/A 0.0 ppb (0) 31.0 ppb (24) 0.11 ppb (1) N/A 3.0 μg/m3 (12) 24.0
 
May 26, 2019, 6 a.m. 2.0 ppb (2) 0.0 ppb (0) 2.4 ppb (2) 2.0 ppb (2) N/A 0.0 ppb (0) 34.0 ppb (26) 0.12 ppb (1) N/A 4.0 μg/m3 (17) 26.0
 
May 26, 2019, 5 a.m. 1.0 ppb (1) 0.0 ppb (0) 1.8 ppb (2) 1.0 ppb (1) N/A 0.0 ppb (0) 36.0 ppb (28) 0.11 ppb (1) N/A 5.0 μg/m3 (21) 28.0
 
May 26, 2019, 4 a.m. 1.0 ppb (1) 0.0 ppb (0) 1.7 ppb (2) 1.0 ppb (1) N/A 0.0 ppb (0) 39.0 ppb (30) 0.1 ppb (1) N/A 1.0 μg/m3 (4) 30.0
 
May 26, 2019, 3 a.m. 2.0 ppb (2) 0.0 ppb (0) 2.2 ppb (2) 2.0 ppb (2) N/A 0.0 ppb (0) 38.0 ppb (29) 0.11 ppb (1) N/A 3.0 μg/m3 (12) 29.0
 
May 26, 2019, 2 a.m. 2.0 ppb (2) 0.0 ppb (0) 2.5 ppb (2) 2.0 ppb (2) N/A 0.0 ppb (0) 38.0 ppb (29) 0.14 ppb (2) N/A 2.0 μg/m3 (8) 29.0
 
May 26, 2019, 1 a.m. 3.0 ppb (3) 0.0 ppb (0) 3.3 ppb (3) 3.0 ppb (3) N/A 0.0 ppb (0) 39.0 ppb (30) 0.17 ppb (2) N/A 2.0 μg/m3 (8) 30.0
 
May 26, 2019, midnight 5.0 ppb (5) 0.0 ppb (0) 5.3 ppb (5) 5.0 ppb (5) N/A 0.0 ppb (0) 39.0 ppb (30) 0.22 ppb (2) N/A 4.0 μg/m3 (17) 30.0
 
May 25, 2019, 11 p.m. 5.0 ppb (5) 1.0 ppb (1) 5.3 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 41.0 ppb (32) 0.22 ppb (2) N/A 5.0 μg/m3 (21) 32.0
 
May 25, 2019, 10 p.m. 5.0 ppb (5) 1.0 ppb (1) 5.4 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 42.0 ppb (32) 0.21 ppb (2) N/A 5.0 μg/m3 (21) 32.0
 
May 25, 2019, 9 p.m. 5.0 ppb (5) 1.0 ppb (1) 5.8 ppb (5) 5.0 ppb (5) N/A 0.0 ppb (0) 37.0 ppb (28) 0.18 ppb (2) N/A 5.0 μg/m3 (21) 28.0
 
May 25, 2019, 7 p.m. 5.0 ppb (5) 1.0 ppb (1) 5.7 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 41.0 ppb (32) 0.16 ppb (2) N/A 3.0 μg/m3 (12) 32.0
 
May 25, 2019, 6 p.m. 8.0 ppb (7) 2.0 ppb (2) 8.5 ppb (8) 6.0 ppb (6) N/A 0.0 ppb (0) 40.0 ppb (31) 0.28 ppb (3) N/A 4.0 μg/m3 (17) 31.0
 
May 25, 2019, 5 p.m. 7.0 ppb (6) 1.0 ppb (1) 7.5 ppb (7) 5.0 ppb (5) N/A 0.0 ppb (0) 41.0 ppb (32) 0.21 ppb (2) N/A 5.0 μg/m3 (21) 32.0
 
May 25, 2019, 4 p.m. 3.0 ppb (3) 1.0 ppb (1) 3.8 ppb (4) 2.0 ppb (2) N/A 0.0 ppb (0) 42.0 ppb (32) 0.14 ppb (2) N/A 5.0 μg/m3 (21) 32.0
 
May 25, 2019, 3 p.m. 2.0 ppb (2) 1.0 ppb (1) 2.8 ppb (3) 2.0 ppb (2) N/A 0.0 ppb (0) 41.0 ppb (32) 0.14 ppb (2) N/A 5.0 μg/m3 (21) 32.0
 
May 25, 2019, 2 p.m. 3.0 ppb (3) 1.0 ppb (1) 2.8 ppb (3) 2.0 ppb (2) N/A 0.0 ppb (0) 37.0 ppb (28) 0.13 ppb (1) N/A 8.0 μg/m3 (33) 33.0
 
May 25, 2019, 1 p.m. 9.0 ppb (8) 3.0 ppb (3) 9.7 ppb (9) 6.0 ppb (6) N/A 0.0 ppb (0) 29.0 ppb (22) 0.16 ppb (2) N/A 7.0 μg/m3 (29) 29.0
 
May 25, 2019, noon 9.0 ppb (8) 3.0 ppb (3) 10.4 ppb (10) 6.0 ppb (6) N/A 0.0 ppb (0) 24.0 ppb (18) 0.22 ppb (2) N/A 9.0 μg/m3 (38) 38.0
 
May 25, 2019, 11 a.m. 14.0 ppb (13) 5.0 ppb (5) 14.6 ppb (14) 9.0 ppb (8) N/A 0.0 ppb (0) 21.0 ppb (16) 0.19 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
May 25, 2019, 10 a.m. 14.0 ppb (13) 3.0 ppb (3) 13.8 ppb (13) 11.0 ppb (10) N/A 0.0 ppb (0) 17.0 ppb (13) N/A N/A 7.0 μg/m3 (29) 29.0
 
May 25, 2019, 9 a.m. 10.0 ppb (9) 1.0 ppb (1) 10.8 ppb (10) 9.0 ppb (8) N/A 0.0 ppb (0) 18.0 ppb (14) 0.22 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
May 25, 2019, 8 a.m. 8.0 ppb (7) 0.0 ppb (0) 7.9 ppb (7) 7.0 ppb (6) N/A 0.0 ppb (0) N/A 0.24 ppb (3) N/A 5.0 μg/m3 (21) 21.0
 
May 25, 2019, 7 a.m. N/A N/A 7.1 ppb (7) N/A N/A 0.0 ppb (0) 25.0 ppb (19) 0.34 ppb (4) N/A 6.0 μg/m3 (25) 25.0
 
May 25, 2019, 6 a.m. N/A N/A 8.7 ppb (8) N/A N/A 0.0 ppb (0) 22.0 ppb (17) 0.3 ppb (3) N/A 8.0 μg/m3 (33) 33.0
 
May 25, 2019, 5 a.m. N/A N/A 11.6 ppb (11) N/A N/A 0.0 ppb (0) 20.0 ppb (15) 0.21 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
May 25, 2019, 4 a.m. 10.0 ppb (9) 0.0 ppb (0) 10.6 ppb (10) 10.0 ppb (9) N/A 0.0 ppb (0) 23.0 ppb (18) 0.2 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
May 25, 2019, 3 a.m. 6.0 ppb (6) 0.0 ppb (0) 6.3 ppb (6) 6.0 ppb (6) N/A 0.0 ppb (0) 31.0 ppb (24) 0.14 ppb (2) N/A 5.0 μg/m3 (21) 24.0
 
May 25, 2019, 2 a.m. 7.0 ppb (6) 1.0 ppb (1) 6.9 ppb (6) 6.0 ppb (6) N/A 0.0 ppb (0) 32.0 ppb (25) 0.13 ppb (1) N/A 7.0 μg/m3 (29) 29.0
 
May 25, 2019, 1 a.m. 10.0 ppb (9) 1.0 ppb (1) 10.6 ppb (10) 9.0 ppb (8) N/A 0.0 ppb (0) 31.0 ppb (24) 0.15 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
May 25, 2019, midnight 19.0 ppb (18) 1.0 ppb (1) 18.7 ppb (17) 18.0 ppb (17) N/A 0.0 ppb (0) 25.0 ppb (19) 0.21 ppb (2) N/A 5.0 μg/m3 (21) 21.0
 
May 24, 2019, 11 p.m. 12.0 ppb (11) 1.0 ppb (1) 11.9 ppb (11) 11.0 ppb (10) N/A 0.0 ppb (0) 31.0 ppb (24) 0.19 ppb (2) N/A 4.0 μg/m3 (17) 24.0
 
May 24, 2019, 10 p.m. 7.0 ppb (6) 1.0 ppb (1) 7.0 ppb (6) 6.0 ppb (6) N/A 0.0 ppb (0) 30.0 ppb (23) 0.15 ppb (2) N/A 3.0 μg/m3 (12) 23.0
 
May 24, 2019, 9 p.m. 6.0 ppb (6) 1.0 ppb (1) 5.1 ppb (5) 5.0 ppb (5) N/A 0.0 ppb (0) 29.0 ppb (22) 0.14 ppb (2) N/A -1.0 μg/m3 (0) 22.0
 
May 24, 2019, 8 p.m. 7.0 ppb (6) 2.0 ppb (2) 7.7 ppb (7) 6.0 ppb (6) N/A 0.0 ppb (0) 26.0 ppb (20) 0.19 ppb (2) N/A 2.0 μg/m3 (8) 20.0
 
May 24, 2019, 7 p.m. 11.0 ppb (10) 2.0 ppb (2) 11.1 ppb (10) 9.0 ppb (8) N/A 0.0 ppb (0) 26.0 ppb (20) 0.18 ppb (2) N/A 4.0 μg/m3 (17) 20.0
 
May 24, 2019, 6 p.m. 4.0 ppb (4) 0.0 ppb (0) 4.0 ppb (4) 3.0 ppb (3) N/A 0.0 ppb (0) 41.0 ppb (32) 0.15 ppb (2) N/A 6.0 μg/m3 (25) 32.0
 
May 24, 2019, 5 p.m. 4.0 ppb (4) 1.0 ppb (1) 4.5 ppb (4) 3.0 ppb (3) N/A 0.0 ppb (0) 44.0 ppb (34) 0.14 ppb (2) N/A 6.0 μg/m3 (25) 34.0
 
May 24, 2019, 4 p.m. 4.0 ppb (4) 1.0 ppb (1) 4.8 ppb (4) 3.0 ppb (3) N/A 0.0 ppb (0) 44.0 ppb (34) 0.14 ppb (2) N/A 5.0 μg/m3 (21) 34.0
 
May 24, 2019, 3 p.m. 5.0 ppb (5) 1.0 ppb (1) 5.5 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 43.0 ppb (33) 0.14 ppb (2) N/A 3.0 μg/m3 (12) 33.0
 
May 24, 2019, 2 p.m. 9.0 ppb (8) 3.0 ppb (3) 9.2 ppb (9) 6.0 ppb (6) N/A 0.0 ppb (0) 35.0 ppb (27) 0.15 ppb (2) N/A 3.0 μg/m3 (12) 27.0
 
May 24, 2019, 1 p.m. 11.0 ppb (10) 4.0 ppb (4) 12.1 ppb (11) 7.0 ppb (6) N/A 0.0 ppb (0) 32.0 ppb (25) 0.16 ppb (2) N/A 5.0 μg/m3 (21) 25.0
 
May 24, 2019, noon 8.0 ppb (7) 2.0 ppb (2) 8.3 ppb (8) 6.0 ppb (6) N/A 0.0 ppb (0) 32.0 ppb (25) 0.16 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
May 24, 2019, 11 a.m. 8.0 ppb (7) 2.0 ppb (2) 8.1 ppb (8) 6.0 ppb (6) N/A 0.0 ppb (0) 32.0 ppb (25) 0.16 ppb (2) N/A 7.0 μg/m3 (29) 29.0
 
May 24, 2019, 10 a.m. 11.0 ppb (10) 3.0 ppb (3) 11.0 ppb (10) 8.0 ppb (7) N/A N/A 29.0 ppb (22) 0.19 ppb (2) N/A 5.0 μg/m3 (21) 22.0
 
May 24, 2019, 9 a.m. 5.0 ppb (5) 1.0 ppb (1) 5.0 ppb (5) 4.0 ppb (4) N/A N/A 30.0 ppb (23) 0.2 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
May 24, 2019, 8 a.m. 3.0 ppb (3) 0.0 ppb (0) N/A 3.0 ppb (3) N/A N/A 32.0 ppb (25) 0.16 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
May 24, 2019, 7 a.m. 2.0 ppb (2) 0.0 ppb (0) N/A 2.0 ppb (2) N/A 0.0 ppb (0) 35.0 ppb (27) 0.15 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
May 24, 2019, 6 a.m. 3.0 ppb (3) 0.0 ppb (0) N/A 3.0 ppb (3) N/A 0.0 ppb (0) 39.0 ppb (30) 0.15 ppb (2) N/A 4.0 μg/m3 (17) 30.0
 
May 24, 2019, 5 a.m. 3.0 ppb (3) 0.0 ppb (0) N/A 3.0 ppb (3) N/A 0.0 ppb (0) 34.0 ppb (26) 0.15 ppb (2) N/A 5.0 μg/m3 (21) 26.0
 
May 24, 2019, 4 a.m. 4.0 ppb (4) 0.0 ppb (0) 4.9 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 31.0 ppb (24) 0.15 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
May 24, 2019, 3 a.m. 4.0 ppb (4) 0.0 ppb (0) 4.7 ppb (4) 4.0 ppb (4) N/A 0.0 ppb (0) 32.0 ppb (25) 0.15 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
May 24, 2019, 2 a.m. 4.0 ppb (4) 0.0 ppb (0) 4.7 ppb (4) 4.0 ppb (4) N/A 0.0 ppb (0) 32.0 ppb (25) 0.15 ppb (2) N/A 5.0 μg/m3 (21) 25.0
 
May 24, 2019, 1 a.m. 5.0 ppb (5) 0.0 ppb (0) 6.1 ppb (6) 5.0 ppb (5) N/A 0.0 ppb (0) 30.0 ppb (23) 0.21 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
May 24, 2019, midnight 4.0 ppb (4) 0.0 ppb (0) 5.2 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 32.0 ppb (25) 0.17 ppb (2) N/A 5.0 μg/m3 (21) 25.0
 
May 23, 2019, 11 p.m. 5.0 ppb (5) 1.0 ppb (1) 4.9 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 34.0 ppb (26) 0.19 ppb (2) N/A 6.0 μg/m3 (25) 26.0
 
May 23, 2019, 10 p.m. 6.0 ppb (6) 1.0 ppb (1) 5.8 ppb (5) 5.0 ppb (5) N/A 0.0 ppb (0) 34.0 ppb (26) 0.24 ppb (3) N/A 6.0 μg/m3 (25) 26.0
 
May 23, 2019, 9 p.m. 6.0 ppb (6) 1.0 ppb (1) 6.7 ppb (6) 5.0 ppb (5) N/A 0.0 ppb (0) 38.0 ppb (29) 0.21 ppb (2) N/A 4.0 μg/m3 (17) 29.0
 
May 23, 2019, 8 p.m. 6.0 ppb (6) 1.0 ppb (1) 6.8 ppb (6) 5.0 ppb (5) N/A 0.0 ppb (0) 40.0 ppb (31) 0.19 ppb (2) N/A 5.0 μg/m3 (21) 31.0
 
May 23, 2019, 7 p.m. 5.0 ppb (5) 1.0 ppb (1) 5.5 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 42.0 ppb (32) 0.17 ppb (2) N/A 6.0 μg/m3 (25) 32.0
 
May 23, 2019, 6 p.m. 5.0 ppb (5) 1.0 ppb (1) 5.3 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 45.0 ppb (35) 0.17 ppb (2) N/A 7.0 μg/m3 (29) 35.0
 
May 23, 2019, 5 p.m. 6.0 ppb (6) 1.0 ppb (1) 6.2 ppb (6) 4.0 ppb (4) N/A 0.0 ppb (0) 42.0 ppb (32) 0.18 ppb (2) N/A 9.0 μg/m3 (38) 38.0
 
May 23, 2019, 4 p.m. 8.0 ppb (7) 2.0 ppb (2) 8.1 ppb (8) 5.0 ppb (5) N/A 0.0 ppb (0) 40.0 ppb (31) 0.19 ppb (2) N/A 13.0 μg/m3 (52) 52.0
 
May 23, 2019, 3 p.m. 10.0 ppb (9) 3.0 ppb (3) 10.0 ppb (9) 7.0 ppb (6) N/A 0.0 ppb (0) 35.0 ppb (27) 0.19 ppb (2) N/A 6.0 μg/m3 (25) 27.0
 
May 23, 2019, 2 p.m. 9.0 ppb (8) 3.0 ppb (3) 9.3 ppb (9) 6.0 ppb (6) N/A 0.0 ppb (0) 33.0 ppb (25) 0.18 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
May 23, 2019, 1 p.m. 8.0 ppb (7) 2.0 ppb (2) 8.2 ppb (8) 5.0 ppb (5) N/A 0.0 ppb (0) 33.0 ppb (25) 0.16 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
May 23, 2019, noon 8.0 ppb (7) 2.0 ppb (2) 8.0 ppb (7) 6.0 ppb (6) N/A 0.0 ppb (0) 31.0 ppb (24) 0.16 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
May 23, 2019, 11 a.m. 8.0 ppb (7) 2.0 ppb (2) 8.3 ppb (8) 7.0 ppb (6) N/A 0.0 ppb (0) 29.0 ppb (22) 0.15 ppb (2) N/A 5.0 μg/m3 (21) 22.0
 
May 23, 2019, 10 a.m. 9.0 ppb (8) 2.0 ppb (2) 8.7 ppb (8) 8.0 ppb (7) N/A 0.0 ppb (0) 27.0 ppb (21) 0.14 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
May 23, 2019, 9 a.m. 4.0 ppb (4) 0.0 ppb (0) 3.9 ppb (4) 3.0 ppb (3) N/A 0.0 ppb (0) 29.0 ppb (22) 0.11 ppb (1) N/A 6.0 μg/m3 (25) 25.0
 
May 23, 2019, 8 a.m. 5.0 ppb (5) 1.0 ppb (1) 6.2 ppb (6) 4.0 ppb (4) N/A 0.0 ppb (0) 27.0 ppb (21) 0.11 ppb (1) N/A 4.0 μg/m3 (17) 21.0
 
May 23, 2019, 7 a.m. 2.0 ppb (2) 0.0 ppb (0) 2.5 ppb (2) 2.0 ppb (2) N/A 0.0 ppb (0) 29.0 ppb (22) 0.11 ppb (1) N/A 6.0 μg/m3 (25) 25.0
 
May 23, 2019, 6 a.m. 2.0 ppb (2) 0.0 ppb (0) 2.8 ppb (3) 2.0 ppb (2) N/A 0.0 ppb (0) 29.0 ppb (22) 0.12 ppb (1) N/A 7.0 μg/m3 (29) 29.0
 
May 23, 2019, 5 a.m. 4.0 ppb (4) 0.0 ppb (0) 4.5 ppb (4) 4.0 ppb (4) N/A 0.0 ppb (0) 27.0 ppb (21) 0.12 ppb (1) N/A 8.0 μg/m3 (33) 33.0
 
May 23, 2019, 4 a.m. 4.0 ppb (4) 0.0 ppb (0) 4.3 ppb (4) 4.0 ppb (4) N/A 0.0 ppb (0) 30.0 ppb (23) 0.13 ppb (1) N/A 4.0 μg/m3 (17) 23.0
 
May 23, 2019, 3 a.m. 4.0 ppb (4) 0.0 ppb (0) 4.5 ppb (4) 4.0 ppb (4) N/A 0.0 ppb (0) 32.0 ppb (25) 0.14 ppb (2) N/A 5.0 μg/m3 (21) 25.0
 
May 23, 2019, 2 a.m. 6.0 ppb (6) 0.0 ppb (0) 6.2 ppb (6) 5.0 ppb (5) N/A 0.0 ppb (0) 32.0 ppb (25) 0.15 ppb (2) N/A 5.0 μg/m3 (21) 25.0
 
May 23, 2019, 1 a.m. 9.0 ppb (8) 1.0 ppb (1) 8.7 ppb (8) 8.0 ppb (7) N/A 0.0 ppb (0) 29.0 ppb (22) 0.19 ppb (2) N/A 3.0 μg/m3 (12) 22.0
 
May 23, 2019, midnight 8.0 ppb (7) 1.0 ppb (1) 8.3 ppb (8) 7.0 ppb (6) N/A 0.0 ppb (0) 29.0 ppb (22) 0.19 ppb (2) N/A 1.0 μg/m3 (4) 22.0
 
May 22, 2019, 11 p.m. 7.0 ppb (6) 1.0 ppb (1) 7.4 ppb (7) 6.0 ppb (6) N/A 0.0 ppb (0) 31.0 ppb (24) 0.17 ppb (2) N/A 0.0 μg/m3 (0) 24.0
 
May 22, 2019, 10 p.m. 8.0 ppb (7) 2.0 ppb (2) 8.2 ppb (8) 6.0 ppb (6) N/A 0.0 ppb (0) 32.0 ppb (25) 0.17 ppb (2) N/A 3.0 μg/m3 (12) 25.0
 
May 22, 2019, 9 p.m. 5.0 ppb (5) 2.0 ppb (2) 5.9 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 33.0 ppb (25) 0.14 ppb (2) N/A 2.0 μg/m3 (8) 25.0
 
May 22, 2019, 8 p.m. 7.0 ppb (6) 2.0 ppb (2) 7.5 ppb (7) 5.0 ppb (5) N/A 0.0 ppb (0) 33.0 ppb (25) 0.15 ppb (2) N/A 4.0 μg/m3 (17) 25.0
 
May 22, 2019, 7 p.m. 8.0 ppb (7) 3.0 ppb (3) 7.6 ppb (7) 5.0 ppb (5) N/A 0.0 ppb (0) 34.0 ppb (26) 0.17 ppb (2) N/A 5.0 μg/m3 (21) 26.0
 
May 22, 2019, 6 p.m. 9.0 ppb (8) 3.0 ppb (3) 8.8 ppb (8) 5.0 ppb (5) N/A 0.0 ppb (0) 34.0 ppb (26) 0.17 ppb (2) N/A 3.0 μg/m3 (12) 26.0
 
May 22, 2019, 5 p.m. 4.0 ppb (4) 1.0 ppb (1) 4.3 ppb (4) 3.0 ppb (3) N/A 0.0 ppb (0) 41.0 ppb (32) 0.12 ppb (1) N/A 4.0 μg/m3 (17) 32.0
 
May 22, 2019, 4 p.m. 4.0 ppb (4) 1.0 ppb (1) 4.0 ppb (4) 3.0 ppb (3) N/A 0.0 ppb (0) 38.0 ppb (29) 0.12 ppb (1) N/A 2.0 μg/m3 (8) 29.0
 
May 22, 2019, 3 p.m. 4.0 ppb (4) 1.0 ppb (1) 4.2 ppb (4) 3.0 ppb (3) N/A 0.0 ppb (0) 36.0 ppb (28) 0.12 ppb (1) N/A 4.0 μg/m3 (17) 28.0
 
May 22, 2019, 2 p.m. 7.0 ppb (6) 3.0 ppb (3) 7.4 ppb (7) 5.0 ppb (5) N/A 0.0 ppb (0) 32.0 ppb (25) 0.13 ppb (1) N/A 7.0 μg/m3 (29) 29.0
 
May 22, 2019, 1 p.m. 6.0 ppb (6) 2.0 ppb (2) 6.6 ppb (6) 4.0 ppb (4) N/A 0.0 ppb (0) 31.0 ppb (24) 0.13 ppb (1) N/A N/A 24.0
 
May 22, 2019, noon 6.0 ppb (6) 2.0 ppb (2) 6.5 ppb (6) 4.0 ppb (4) N/A 0.0 ppb (0) 31.0 ppb (24) 0.13 ppb (1) N/A 6.0 μg/m3 (25) 25.0
 
May 22, 2019, 11 a.m. 6.0 ppb (6) 2.0 ppb (2) 6.0 ppb (6) 4.0 ppb (4) N/A 0.0 ppb (0) 32.0 ppb (25) 0.13 ppb (1) N/A 6.0 μg/m3 (25) 25.0
 
May 22, 2019, 10 a.m. 7.0 ppb (6) 1.0 ppb (1) 6.6 ppb (6) 5.0 ppb (5) N/A 0.0 ppb (0) 30.0 ppb (23) N/A N/A 5.0 μg/m3 (21) 23.0
 
May 22, 2019, 9 a.m. 12.0 ppb (11) 3.0 ppb (3) 11.6 ppb (11) 10.0 ppb (9) N/A 0.0 ppb (0) 27.0 ppb (21) 0.15 ppb (2) N/A 3.0 μg/m3 (12) 21.0
 
May 22, 2019, 8 a.m. 8.0 ppb (7) 1.0 ppb (1) 7.9 ppb (7) 7.0 ppb (6) N/A 0.0 ppb (0) N/A 0.12 ppb (1) N/A 1.0 μg/m3 (4) 7.0
 
May 22, 2019, 7 a.m. N/A N/A 16.1 ppb (15) N/A N/A 0.0 ppb (0) 24.0 ppb (18) 0.16 ppb (2) N/A 4.0 μg/m3 (17) 18.0
 
May 22, 2019, 6 a.m. N/A N/A 9.5 ppb (9) N/A N/A 0.0 ppb (0) 28.0 ppb (22) 0.13 ppb (1) N/A 6.0 μg/m3 (25) 25.0
 
May 22, 2019, 5 a.m. N/A N/A 9.4 ppb (9) N/A N/A 0.0 ppb (0) 30.0 ppb (23) 0.15 ppb (2) N/A 4.0 μg/m3 (17) 23.0
 
May 22, 2019, 4 a.m. 15.0 ppb (14) 3.0 ppb (3) 15.7 ppb (15) 12.0 ppb (11) N/A 0.0 ppb (0) 27.0 ppb (21) 0.15 ppb (2) N/A 4.0 μg/m3 (17) 21.0
 
May 22, 2019, 3 a.m. 10.0 ppb (9) 2.0 ppb (2) 11.7 ppb (11) 9.0 ppb (8) N/A 0.0 ppb (0) 31.0 ppb (24) 0.16 ppb (2) N/A 5.0 μg/m3 (21) 24.0
 
May 22, 2019, 2 a.m. 11.0 ppb (10) 2.0 ppb (2) 11.1 ppb (10) 9.0 ppb (8) N/A 0.0 ppb (0) 31.0 ppb (24) 0.16 ppb (2) N/A 2.0 μg/m3 (8) 24.0
 
May 22, 2019, 1 a.m. 7.0 ppb (6) 1.0 ppb (1) 8.5 ppb (8) 6.0 ppb (6) N/A 0.0 ppb (0) 33.0 ppb (25) 0.14 ppb (2) N/A 1.0 μg/m3 (4) 25.0
 
May 22, 2019, midnight 7.0 ppb (6) 1.0 ppb (1) 6.7 ppb (6) 6.0 ppb (6) N/A 0.0 ppb (0) 35.0 ppb (27) 0.12 ppb (1) N/A 2.0 μg/m3 (8) 27.0
 
May 21, 2019, 11 p.m. 6.0 ppb (6) 1.0 ppb (1) 6.6 ppb (6) 5.0 ppb (5) N/A 0.0 ppb (0) 35.0 ppb (27) 0.14 ppb (2) N/A 3.0 μg/m3 (12) 27.0
 
May 21, 2019, 10 p.m. 5.0 ppb (5) 1.0 ppb (1) 5.2 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 35.0 ppb (27) 0.12 ppb (1) N/A 4.0 μg/m3 (17) 27.0
 
May 21, 2019, 9 p.m. 7.0 ppb (6) 2.0 ppb (2) 6.9 ppb (6) 5.0 ppb (5) N/A 0.0 ppb (0) 35.0 ppb (27) 0.13 ppb (1) N/A 6.0 μg/m3 (25) 27.0
 
May 21, 2019, 8 p.m. 10.0 ppb (9) 3.0 ppb (3) 11.0 ppb (10) 6.0 ppb (6) N/A 0.0 ppb (0) 35.0 ppb (27) 0.13 ppb (1) N/A 4.0 μg/m3 (17) 27.0
 
May 21, 2019, 7 p.m. 7.0 ppb (6) 2.0 ppb (2) 6.8 ppb (6) 4.0 ppb (4) N/A 0.0 ppb (0) 34.0 ppb (26) 0.13 ppb (1) N/A 4.0 μg/m3 (17) 26.0
 
May 21, 2019, 6 p.m. 9.0 ppb (8) 3.0 ppb (3) 9.1 ppb (8) 5.0 ppb (5) N/A 0.0 ppb (0) 32.0 ppb (25) 0.14 ppb (2) N/A 4.0 μg/m3 (17) 25.0
 
May 21, 2019, 5 p.m. 9.0 ppb (8) 4.0 ppb (4) 8.9 ppb (8) 5.0 ppb (5) N/A 0.0 ppb (0) 31.0 ppb (24) 0.13 ppb (1) N/A 7.0 μg/m3 (29) 29.0
 
May 21, 2019, 4 p.m. 8.0 ppb (7) 3.0 ppb (3) 8.6 ppb (8) 5.0 ppb (5) N/A 0.0 ppb (0) 30.0 ppb (23) 0.12 ppb (1) N/A 5.0 μg/m3 (21) 23.0
 
May 21, 2019, 3 p.m. 9.0 ppb (8) 4.0 ppb (4) 9.0 ppb (8) 5.0 ppb (5) N/A 0.0 ppb (0) 31.0 ppb (24) 0.12 ppb (1) N/A 4.0 μg/m3 (17) 24.0
 
May 21, 2019, 2 p.m. 7.0 ppb (6) 3.0 ppb (3) 7.5 ppb (7) 4.0 ppb (4) N/A 0.0 ppb (0) 29.0 ppb (22) 0.13 ppb (1) N/A 4.0 μg/m3 (17) 22.0
 
May 21, 2019, 1 p.m. 7.0 ppb (6) 3.0 ppb (3) 7.5 ppb (7) 4.0 ppb (4) N/A 0.0 ppb (0) 26.0 ppb (20) 0.14 ppb (2) N/A 5.0 μg/m3 (21) 21.0
 
May 21, 2019, noon 10.0 ppb (9) 5.0 ppb (5) 10.7 ppb (10) 5.0 ppb (5) N/A 0.0 ppb (0) 21.0 ppb (16) 0.14 ppb (2) N/A 5.0 μg/m3 (21) 21.0
 
May 21, 2019, 11 a.m. 10.0 ppb (9) 4.0 ppb (4) 10.7 ppb (10) 6.0 ppb (6) N/A 0.0 ppb (0) 21.0 ppb (16) 0.14 ppb (2) N/A 4.0 μg/m3 (17) 17.0
 
May 21, 2019, 10 a.m. 13.0 ppb (12) 5.0 ppb (5) 11.8 ppb (11) 8.0 ppb (7) N/A N/A 21.0 ppb (16) 0.13 ppb (1) N/A 5.0 μg/m3 (21) 21.0
 
May 21, 2019, 9 a.m. 8.0 ppb (7) 2.0 ppb (2) 8.3 ppb (8) 6.0 ppb (6) N/A N/A 21.0 ppb (16) 0.12 ppb (1) N/A 5.0 μg/m3 (21) 21.0
 
May 21, 2019, 8 a.m. 4.0 ppb (4) 1.0 ppb (1) N/A 3.0 ppb (3) N/A N/A 26.0 ppb (20) 0.11 ppb (1) N/A 5.0 μg/m3 (21) 21.0
 
May 21, 2019, 7 a.m. 9.0 ppb (8) 2.0 ppb (2) N/A 8.0 ppb (7) N/A 0.0 ppb (0) 26.0 ppb (20) 0.12 ppb (1) N/A 1.0 μg/m3 (4) 20.0
 
May 21, 2019, 6 a.m. 7.0 ppb (6) 1.0 ppb (1) N/A 6.0 ppb (6) N/A 0.0 ppb (0) 31.0 ppb (24) 0.12 ppb (1) N/A 1.0 μg/m3 (4) 24.0
 
May 21, 2019, 5 a.m. 11.0 ppb (10) 2.0 ppb (2) N/A 9.0 ppb (8) N/A 0.0 ppb (0) 29.0 ppb (22) 0.12 ppb (1) N/A 0.0 μg/m3 (0) 22.0
 
May 21, 2019, 4 a.m. 11.0 ppb (10) 2.0 ppb (2) 11.3 ppb (10) 9.0 ppb (8) N/A 0.0 ppb (0) 31.0 ppb (24) 0.13 ppb (1) N/A 4.0 μg/m3 (17) 24.0
 
May 21, 2019, 3 a.m. 6.0 ppb (6) 0.0 ppb (0) 7.7 ppb (7) 6.0 ppb (6) N/A 0.0 ppb (0) 32.0 ppb (25) 0.22 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
May 21, 2019, 2 a.m. 5.0 ppb (5) 0.0 ppb (0) 6.3 ppb (6) 5.0 ppb (5) N/A 0.0 ppb (0) 38.0 ppb (29) 0.2 ppb (2) N/A 6.0 μg/m3 (25) 29.0
 
May 21, 2019, 1 a.m. 6.0 ppb (6) 0.0 ppb (0) 7.1 ppb (7) 6.0 ppb (6) N/A 0.0 ppb (0) 38.0 ppb (29) 0.24 ppb (3) N/A 7.0 μg/m3 (29) 29.0
 
May 21, 2019, midnight 5.0 ppb (5) 0.0 ppb (0) 5.7 ppb (5) 5.0 ppb (5) N/A 0.0 ppb (0) 40.0 ppb (31) 0.24 ppb (3) N/A 9.0 μg/m3 (38) 38.0
 
May 20, 2019, 11 p.m. 5.0 ppb (5) 0.0 ppb (0) 5.7 ppb (5) 5.0 ppb (5) N/A 0.0 ppb (0) 44.0 ppb (34) 0.24 ppb (3) N/A 9.0 μg/m3 (38) 38.0
 
May 20, 2019, 10 p.m. 5.0 ppb (5) 0.0 ppb (0) 6.1 ppb (6) 5.0 ppb (5) N/A 0.0 ppb (0) 47.0 ppb (36) 0.23 ppb (3) N/A 9.0 μg/m3 (38) 38.0
 
May 20, 2019, 9 p.m. 7.0 ppb (6) 1.0 ppb (1) 7.6 ppb (7) 6.0 ppb (6) N/A 0.0 ppb (0) 49.0 ppb (38) 0.23 ppb (3) N/A 9.0 μg/m3 (38) 38.0
 
May 20, 2019, 8 p.m. 7.0 ppb (6) 1.0 ppb (1) 7.6 ppb (7) 6.0 ppb (6) N/A 0.0 ppb (0) 50.0 ppb (38) 0.22 ppb (2) N/A 15.0 μg/m3 (56) 56.0
 
May 20, 2019, 7 p.m. 5.0 ppb (5) 1.0 ppb (1) 6.6 ppb (6) 5.0 ppb (5) N/A 0.0 ppb (0) 52.0 ppb (40) 0.19 ppb (2) N/A 6.0 μg/m3 (25) 40.0
 
May 20, 2019, 6 p.m. 6.0 ppb (6) 1.0 ppb (1) 7.7 ppb (7) 5.0 ppb (5) N/A N/A 49.0 ppb (38) 0.19 ppb (2) N/A 8.0 μg/m3 (33) 38.0
 
May 20, 2019, 5 p.m. 5.0 ppb (5) 1.0 ppb (1) 6.6 ppb (6) 4.0 ppb (4) N/A N/A 48.0 ppb (37) 0.22 ppb (2) N/A 15.0 μg/m3 (56) 56.0
 
May 20, 2019, 4 p.m. 6.0 ppb (6) 1.0 ppb (1) 7.8 ppb (7) 5.0 ppb (5) N/A N/A 44.0 ppb (34) 0.24 ppb (3) N/A 17.0 μg/m3 (61) 61.0
 
May 20, 2019, 3 p.m. 6.0 ppb (6) 1.0 ppb (1) 7.0 ppb (6) 5.0 ppb (5) N/A N/A 44.0 ppb (34) 0.2 ppb (2) N/A 16.0 μg/m3 (59) 59.0
 
May 20, 2019, 2 p.m. 7.0 ppb (6) 1.0 ppb (1) 7.9 ppb (7) 5.0 ppb (5) N/A N/A 39.0 ppb (30) 0.22 ppb (2) N/A 15.0 μg/m3 (56) 56.0
 
May 20, 2019, 1 p.m. 12.0 ppb (11) 3.0 ppb (3) 13.4 ppb (12) 9.0 ppb (8) N/A N/A 28.0 ppb (22) 0.25 ppb (3) N/A 13.0 μg/m3 (52) 52.0
 
May 20, 2019, noon 12.0 ppb (11) 2.0 ppb (2) 13.2 ppb (12) 10.0 ppb (9) N/A N/A 28.0 ppb (22) 0.25 ppb (3) N/A 12.0 μg/m3 (50) 50.0
 
May 20, 2019, 11 a.m. 8.0 ppb (7) 1.0 ppb (1) 9.4 ppb (9) 7.0 ppb (6) N/A N/A 33.0 ppb (25) 0.21 ppb (2) N/A 7.0 μg/m3 (29) 29.0
 
May 20, 2019, 10 a.m. 8.0 ppb (7) 1.0 ppb (1) 9.2 ppb (9) 7.0 ppb (6) N/A N/A 34.0 ppb (26) 0.18 ppb (2) N/A 4.0 μg/m3 (17) 26.0
 
May 20, 2019, 9 a.m. 5.0 ppb (5) 1.0 ppb (1) 4.6 ppb (4) 4.0 ppb (4) N/A 1.0 ppb (1) 38.0 ppb (29) 0.15 ppb (2) N/A 6.0 μg/m3 (25) 29.0
 
May 20, 2019, 8 a.m. 3.0 ppb (3) 0.0 ppb (0) 3.4 ppb (3) 3.0 ppb (3) N/A 0.0 ppb (0) 39.0 ppb (30) 0.15 ppb (2) N/A 7.0 μg/m3 (29) 30.0
 
May 20, 2019, 7 a.m. 2.0 ppb (2) 0.0 ppb (0) 2.4 ppb (2) 2.0 ppb (2) N/A 0.0 ppb (0) 42.0 ppb (32) 0.15 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
May 20, 2019, 6 a.m. 1.0 ppb (1) 0.0 ppb (0) 1.8 ppb (2) 1.0 ppb (1) N/A 0.0 ppb (0) 41.0 ppb (32) 0.14 ppb (2) N/A 12.0 μg/m3 (50) 50.0
 
May 20, 2019, 5 a.m. 1.0 ppb (1) 0.0 ppb (0) 1.7 ppb (2) 1.0 ppb (1) N/A 0.0 ppb (0) 42.0 ppb (32) 0.13 ppb (1) N/A 9.0 μg/m3 (38) 38.0
 
May 20, 2019, 4 a.m. 1.0 ppb (1) 0.0 ppb (0) 1.8 ppb (2) 1.0 ppb (1) N/A 0.0 ppb (0) 43.0 ppb (33) 0.13 ppb (1) N/A 8.0 μg/m3 (33) 33.0
 
May 20, 2019, 3 a.m. 2.0 ppb (2) 0.0 ppb (0) 2.2 ppb (2) 2.0 ppb (2) N/A 0.0 ppb (0) 42.0 ppb (32) 0.13 ppb (1) N/A 6.0 μg/m3 (25) 32.0
 
May 20, 2019, 2 a.m. 2.0 ppb (2) 0.0 ppb (0) 2.8 ppb (3) 2.0 ppb (2) N/A 0.0 ppb (0) 40.0 ppb (31) 0.14 ppb (2) N/A 6.0 μg/m3 (25) 31.0
 
May 20, 2019, 1 a.m. 2.0 ppb (2) 0.0 ppb (0) 2.6 ppb (2) 2.0 ppb (2) N/A 0.0 ppb (0) 40.0 ppb (31) 0.17 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
May 20, 2019, midnight 3.0 ppb (3) 0.0 ppb (0) 3.9 ppb (4) 3.0 ppb (3) N/A 0.0 ppb (0) 38.0 ppb (29) 0.19 ppb (2) N/A 5.0 μg/m3 (21) 29.0
 
May 19, 2019, 11 p.m. 3.0 ppb (3) 0.0 ppb (0) 3.6 ppb (3) 3.0 ppb (3) N/A 0.0 ppb (0) 38.0 ppb (29) 0.18 ppb (2) N/A 6.0 μg/m3 (25) 29.0