AQSQID: 060376012

Site Name: Santa Clarita

Location: Santa Clarita, CA

Reporting: True, Located: True

Current AQI: 31.0

Santa Clarita CA, US: 34.3833, -118.5283

Date Observed (UTC) NOX NO NOY NO2 NO2Y SO2 OZONE CO PM10 PM2.5 AQI AQI/500
March 25, 2019, 8 a.m. 7.7 ppb (7) 0.2 ppb (0) N/A 7.0 ppb (6) N/A N/A 8.0 ppb (6) 0.31 ppb (3) N/A 7.5 μg/m3 (31) 31.0
 
March 25, 2019, 7 a.m. 9.9 ppb (9) 0.1 ppb (0) N/A 10.0 ppb (9) N/A N/A 7.0 ppb (5) 0.37 ppb (4) N/A 2.8 μg/m3 (12) 12.0
 
March 25, 2019, 6 a.m. 10.1 ppb (9) 0.5 ppb (0) N/A 10.0 ppb (9) N/A N/A 8.0 ppb (6) 0.35 ppb (4) N/A 2.8 μg/m3 (12) 12.0
 
March 25, 2019, 5 a.m. 11.5 ppb (11) 0.3 ppb (0) N/A 11.0 ppb (10) N/A N/A 11.0 ppb (8) 0.31 ppb (3) N/A 6.8 μg/m3 (28) 28.0
 
March 25, 2019, 4 a.m. 10.0 ppb (9) 0.2 ppb (0) N/A 10.0 ppb (9) N/A N/A 16.0 ppb (12) 0.28 ppb (3) N/A 6.8 μg/m3 (28) 28.0
 
March 25, 2019, 3 a.m. 5.3 ppb (5) 0.1 ppb (0) N/A 5.0 ppb (5) N/A N/A 27.0 ppb (21) 0.17 ppb (2) N/A 19.0 μg/m3 (65) 65.0
 
March 25, 2019, 2 a.m. 5.1 ppb (5) 0.4 ppb (0) N/A 5.0 ppb (5) N/A N/A 35.0 ppb (27) 0.18 ppb (2) N/A 4.1 μg/m3 (17) 27.0
 
March 25, 2019, 1 a.m. 5.5 ppb (5) 0.5 ppb (0) N/A 5.0 ppb (5) N/A N/A 49.0 ppb (38) 0.2 ppb (2) N/A 7.2 μg/m3 (30) 38.0
 
March 25, 2019, midnight 3.6 ppb (3) 0.1 ppb (0) N/A 3.0 ppb (3) N/A N/A 56.0 ppb (43) 0.21 ppb (2) N/A 7.5 μg/m3 (31) 43.0
 
March 24, 2019, 11 p.m. 3.6 ppb (3) 0.4 ppb (0) N/A 3.0 ppb (3) N/A N/A 59.0 ppb (45) 0.21 ppb (2) N/A 6.0 μg/m3 (25) 45.0
 
March 24, 2019, 10 p.m. 3.8 ppb (4) 0.7 ppb (1) N/A 3.0 ppb (3) N/A N/A 60.0 ppb (46) 0.21 ppb (2) N/A 4.8 μg/m3 (20) 46.0
 
March 24, 2019, 9 p.m. 3.0 ppb (3) 0.1 ppb (0) N/A 3.0 ppb (3) N/A N/A 58.0 ppb (45) 0.22 ppb (2) N/A 2.3 μg/m3 (10) 45.0
 
March 24, 2019, 8 p.m. 3.7 ppb (3) 0.6 ppb (1) N/A 3.0 ppb (3) N/A N/A 54.0 ppb (42) 0.22 ppb (2) N/A 6.5 μg/m3 (27) 42.0
 
March 24, 2019, 7 p.m. 2.9 ppb (3) 0.5 ppb (0) N/A 2.0 ppb (2) N/A N/A 53.0 ppb (41) 0.2 ppb (2) N/A 6.0 μg/m3 (25) 41.0
 
March 24, 2019, 6 p.m. 1.6 ppb (1) 0.3 ppb (0) N/A 1.0 ppb (1) N/A N/A 51.0 ppb (39) 0.18 ppb (2) N/A 2.4 μg/m3 (10) 39.0
 
March 24, 2019, 5 p.m. 3.2 ppb (3) 0.7 ppb (1) N/A 3.0 ppb (3) N/A N/A 44.0 ppb (34) 0.19 ppb (2) N/A 6.8 μg/m3 (28) 34.0
 
March 24, 2019, 4 p.m. 5.0 ppb (5) 1.3 ppb (1) N/A 4.0 ppb (4) N/A N/A 33.0 ppb (25) 0.23 ppb (3) N/A 7.5 μg/m3 (31) 31.0
 
March 24, 2019, 3 p.m. 13.2 ppb (12) 5.3 ppb (5) N/A 8.0 ppb (7) N/A N/A 15.0 ppb (12) 0.35 ppb (4) N/A 10.2 μg/m3 (42) 42.0
 
March 24, 2019, 2 p.m. 11.9 ppb (11) 4.0 ppb (4) N/A 8.0 ppb (7) N/A N/A 7.0 ppb (5) 0.32 ppb (4) N/A 10.5 μg/m3 (44) 44.0
 
March 24, 2019, 1 p.m. 6.5 ppb (6) 0.4 ppb (0) N/A 6.0 ppb (6) N/A N/A 7.0 ppb (5) 0.25 ppb (3) N/A 3.4 μg/m3 (14) 14.0
 
March 24, 2019, noon 6.0 ppb (6) 0.4 ppb (0) N/A 6.0 ppb (6) N/A N/A 10.0 ppb (8) 0.26 ppb (3) N/A 3.9 μg/m3 (16) 16.0
 
March 24, 2019, 11 a.m. 5.3 ppb (5) 0.3 ppb (0) N/A 5.0 ppb (5) N/A N/A 13.0 ppb (10) 0.25 ppb (3) N/A 9.0 μg/m3 (38) 38.0
 
March 24, 2019, 10 a.m. 6.0 ppb (6) 0.4 ppb (0) N/A 6.0 ppb (6) N/A N/A 13.0 ppb (10) 0.26 ppb (3) N/A 7.5 μg/m3 (31) 31.0
 
March 24, 2019, 9 a.m. 3.9 ppb (4) 0.0 ppb (0) N/A 4.0 ppb (4) N/A N/A 14.0 ppb (11) 0.23 ppb (3) N/A 4.6 μg/m3 (19) 19.0
 
March 24, 2019, 8 a.m. 4.6 ppb (4) 0.1 ppb (0) N/A 5.0 ppb (5) N/A N/A 14.0 ppb (11) 0.25 ppb (3) N/A 3.3 μg/m3 (14) 14.0
 
March 24, 2019, 7 a.m. 6.5 ppb (6) 0.3 ppb (0) N/A 6.0 ppb (6) N/A N/A 12.0 ppb (9) 0.26 ppb (3) N/A 2.6 μg/m3 (11) 11.0
 
March 24, 2019, 6 a.m. 7.8 ppb (7) 0.3 ppb (0) N/A 7.0 ppb (6) N/A N/A 10.0 ppb (8) 0.27 ppb (3) N/A 2.8 μg/m3 (12) 12.0
 
March 24, 2019, 5 a.m. 9.5 ppb (9) 0.5 ppb (0) N/A 9.0 ppb (8) N/A N/A 9.0 ppb (7) 0.26 ppb (3) N/A 4.3 μg/m3 (18) 18.0
 
March 24, 2019, 4 a.m. 4.9 ppb (5) 0.3 ppb (0) N/A 5.0 ppb (5) N/A N/A 16.0 ppb (12) 0.2 ppb (2) N/A 3.3 μg/m3 (14) 14.0
 
March 24, 2019, 3 a.m. 4.0 ppb (4) 0.3 ppb (0) N/A 4.0 ppb (4) N/A N/A 25.0 ppb (19) 0.14 ppb (2) N/A 1.6 μg/m3 (7) 19.0
 
March 24, 2019, 2 a.m. 3.1 ppb (3) 0.2 ppb (0) N/A 3.0 ppb (3) N/A N/A 31.0 ppb (24) 0.13 ppb (1) N/A 5.8 μg/m3 (24) 24.0
 
March 24, 2019, 1 a.m. 2.2 ppb (2) 0.1 ppb (0) N/A 2.0 ppb (2) N/A N/A 35.0 ppb (27) 0.11 ppb (1) N/A 4.3 μg/m3 (18) 27.0
 
March 24, 2019, midnight 2.5 ppb (2) 0.5 ppb (0) N/A 2.0 ppb (2) N/A N/A 36.0 ppb (28) 0.12 ppb (1) N/A 3.3 μg/m3 (14) 28.0
 
March 23, 2019, 11 p.m. 3.0 ppb (3) 0.4 ppb (0) N/A 3.0 ppb (3) N/A N/A 39.0 ppb (30) 0.14 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 23, 2019, 10 p.m. 7.8 ppb (7) 1.0 ppb (1) N/A 7.0 ppb (6) N/A N/A 37.0 ppb (28) 0.21 ppb (2) N/A 9.0 μg/m3 (38) 38.0
 
March 23, 2019, 9 p.m. 10.0 ppb (9) 1.7 ppb (2) N/A 8.0 ppb (7) N/A N/A 38.0 ppb (29) 0.22 ppb (2) N/A 7.5 μg/m3 (31) 31.0
 
March 23, 2019, 8 p.m. 8.6 ppb (8) 1.7 ppb (2) N/A 7.0 ppb (6) N/A N/A 41.0 ppb (32) 0.2 ppb (2) N/A 5.5 μg/m3 (23) 32.0
 
March 23, 2019, 7 p.m. 7.0 ppb (6) 1.3 ppb (1) N/A 6.0 ppb (6) N/A N/A 40.0 ppb (31) 0.2 ppb (2) N/A 3.6 μg/m3 (15) 31.0
 
March 23, 2019, 6 p.m. 5.7 ppb (5) 1.4 ppb (1) N/A 4.0 ppb (4) N/A N/A 39.0 ppb (30) 0.19 ppb (2) N/A 1.6 μg/m3 (7) 30.0
 
March 23, 2019, 5 p.m. 5.2 ppb (5) 1.5 ppb (1) N/A 4.0 ppb (4) N/A N/A 38.0 ppb (29) 0.19 ppb (2) N/A 5.5 μg/m3 (23) 29.0
 
March 23, 2019, 4 p.m. 5.2 ppb (5) 1.1 ppb (1) N/A 4.0 ppb (4) N/A N/A 34.0 ppb (26) 0.21 ppb (2) N/A 8.5 μg/m3 (35) 35.0
 
March 23, 2019, 3 p.m. 6.1 ppb (6) 0.5 ppb (0) N/A 6.0 ppb (6) N/A N/A 31.0 ppb (24) 0.24 ppb (3) N/A 8.5 μg/m3 (35) 35.0
 
March 23, 2019, 2 p.m. 6.1 ppb (6) 0.6 ppb (1) N/A 5.0 ppb (5) N/A N/A 32.0 ppb (25) 0.24 ppb (3) N/A 10.2 μg/m3 (42) 42.0
 
March 23, 2019, 1 p.m. 6.2 ppb (6) 0.2 ppb (0) N/A 6.0 ppb (6) N/A N/A 27.0 ppb (21) 0.25 ppb (3) N/A 11.5 μg/m3 (48) 48.0
 
March 23, 2019, noon 5.7 ppb (5) 0.3 ppb (0) N/A 5.0 ppb (5) N/A N/A 30.0 ppb (23) 0.27 ppb (3) N/A 13.7 μg/m3 (54) 54.0
 
March 23, 2019, 11 a.m. 9.9 ppb (9) 0.4 ppb (0) N/A 9.0 ppb (8) N/A N/A 21.0 ppb (16) 0.27 ppb (3) N/A 9.2 μg/m3 (38) 38.0
 
March 23, 2019, 10 a.m. 20.1 ppb (19) 3.2 ppb (3) N/A 17.0 ppb (16) N/A N/A 5.0 ppb (4) 0.32 ppb (4) N/A 6.8 μg/m3 (28) 28.0
 
March 23, 2019, 9 a.m. 17.9 ppb (17) 1.3 ppb (1) N/A 17.0 ppb (16) N/A N/A 4.0 ppb (3) 0.32 ppb (4) N/A 9.7 μg/m3 (40) 40.0
 
March 23, 2019, 8 a.m. 12.6 ppb (12) 0.8 ppb (1) N/A 12.0 ppb (11) N/A N/A 16.0 ppb (12) 0.34 ppb (4) N/A 17.0 μg/m3 (61) 61.0
 
March 23, 2019, 7 a.m. 13.6 ppb (13) 0.5 ppb (0) N/A 13.0 ppb (12) N/A N/A 8.0 ppb (6) 0.38 ppb (4) N/A 4.8 μg/m3 (20) 20.0
 
March 23, 2019, 6 a.m. 12.7 ppb (12) 0.9 ppb (1) N/A 12.0 ppb (11) N/A N/A 9.0 ppb (7) 0.37 ppb (4) N/A 6.3 μg/m3 (26) 26.0
 
March 23, 2019, 5 a.m. 12.4 ppb (11) 0.2 ppb (0) N/A 12.0 ppb (11) N/A N/A 14.0 ppb (11) 0.34 ppb (4) N/A 6.3 μg/m3 (26) 26.0
 
March 23, 2019, 4 a.m. 10.1 ppb (9) 0.2 ppb (0) N/A 10.0 ppb (9) N/A N/A 25.0 ppb (19) 0.28 ppb (3) N/A 5.5 μg/m3 (23) 23.0
 
March 23, 2019, 3 a.m. 9.8 ppb (9) 0.2 ppb (0) N/A 10.0 ppb (9) N/A N/A 34.0 ppb (26) 0.23 ppb (3) N/A 4.3 μg/m3 (18) 26.0
 
March 23, 2019, 2 a.m. 4.2 ppb (4) 0.1 ppb (0) N/A 4.0 ppb (4) N/A N/A 39.0 ppb (30) 0.14 ppb (2) N/A 4.5 μg/m3 (19) 30.0
 
March 23, 2019, 1 a.m. 8.0 ppb (7) 2.5 ppb (2) N/A 5.0 ppb (5) N/A N/A 46.0 ppb (35) 0.16 ppb (2) N/A 4.8 μg/m3 (20) 35.0
 
March 23, 2019, midnight 3.8 ppb (4) 0.3 ppb (0) N/A 4.0 ppb (4) N/A N/A 47.0 ppb (36) 0.15 ppb (2) N/A 5.3 μg/m3 (22) 36.0
 
March 22, 2019, 11 p.m. 3.7 ppb (3) 0.6 ppb (1) N/A 3.0 ppb (3) N/A N/A 49.0 ppb (38) 0.15 ppb (2) N/A 2.8 μg/m3 (12) 38.0
 
March 22, 2019, 10 p.m. 3.1 ppb (3) 0.2 ppb (0) N/A 3.0 ppb (3) N/A N/A 51.0 ppb (39) 0.17 ppb (2) N/A -0.1 μg/m3 (0) 39.0
 
March 22, 2019, 9 p.m. 3.5 ppb (3) 0.4 ppb (0) N/A 3.0 ppb (3) N/A N/A 49.0 ppb (38) 0.17 ppb (2) N/A 1.2 μg/m3 (5) 38.0
 
March 22, 2019, 8 p.m. 5.1 ppb (5) 1.1 ppb (1) N/A 4.0 ppb (4) N/A N/A 46.0 ppb (35) 0.2 ppb (2) N/A 4.3 μg/m3 (18) 35.0
 
March 22, 2019, 7 p.m. 9.3 ppb (9) 2.8 ppb (3) N/A 7.0 ppb (6) N/A N/A 39.0 ppb (30) 0.24 ppb (3) N/A 2.6 μg/m3 (11) 30.0
 
March 22, 2019, 6 p.m. 11.7 ppb (11) 3.8 ppb (4) N/A 8.0 ppb (7) N/A N/A 36.0 ppb (28) 0.24 ppb (3) N/A -1.5 μg/m3 (0) 28.0
 
March 22, 2019, 5 p.m. 8.6 ppb (8) 2.7 ppb (3) N/A 6.0 ppb (6) N/A N/A 38.0 ppb (29) 0.21 ppb (2) N/A 0.5 μg/m3 (2) 29.0
 
March 22, 2019, 4 p.m. 17.7 ppb (16) 6.9 ppb (6) N/A 11.0 ppb (10) N/A N/A 23.0 ppb (18) 0.31 ppb (3) N/A 7.2 μg/m3 (30) 30.0
 
March 22, 2019, 3 p.m. 24.2 ppb (22) 12.2 ppb (11) N/A 12.0 ppb (11) N/A N/A 14.0 ppb (11) 0.39 ppb (4) N/A 12.7 μg/m3 (51) 51.0
 
March 22, 2019, 2 p.m. 40.3 ppb (37) 25.0 ppb (23) N/A 15.0 ppb (14) N/A N/A 3.0 ppb (2) 0.47 ppb (5) N/A N/A 37.0
 
March 22, 2019, 1 p.m. 29.6 ppb (27) 14.8 ppb (14) N/A 15.0 ppb (14) N/A N/A 3.0 ppb (2) 0.42 ppb (5) N/A 5.3 μg/m3 (22) 27.0
 
March 22, 2019, noon 17.4 ppb (16) 3.1 ppb (3) N/A 14.0 ppb (13) N/A N/A 5.0 ppb (4) 0.41 ppb (5) N/A 0.7 μg/m3 (3) 16.0
 
March 22, 2019, 11 a.m. 18.0 ppb (17) 1.9 ppb (2) N/A 16.0 ppb (15) N/A N/A 4.0 ppb (3) 0.28 ppb (3) N/A -4.4 μg/m3 (0) 17.0
 
March 22, 2019, 10 a.m. 21.2 ppb (20) 4.9 ppb (5) N/A 16.0 ppb (15) N/A N/A 3.0 ppb (2) 0.3 ppb (3) N/A -3.4 μg/m3 (0) 20.0
 
March 22, 2019, 9 a.m. 8.0 ppb (7) 0.3 ppb (0) N/A 8.0 ppb (7) N/A N/A 7.0 ppb (5) 0.27 ppb (3) N/A -1.0 μg/m3 (0) 7.0
 
March 22, 2019, 8 a.m. 7.3 ppb (7) 0.4 ppb (0) N/A 7.0 ppb (6) N/A N/A 8.0 ppb (6) 0.29 ppb (3) N/A 2.2 μg/m3 (9) 9.0
 
March 22, 2019, 7 a.m. 7.7 ppb (7) 0.3 ppb (0) N/A 7.0 ppb (6) N/A N/A 10.0 ppb (8) 0.28 ppb (3) N/A 2.3 μg/m3 (10) 10.0
 
March 22, 2019, 6 a.m. 9.0 ppb (8) 0.3 ppb (0) N/A 9.0 ppb (8) N/A N/A 10.0 ppb (8) 0.32 ppb (4) N/A 2.9 μg/m3 (12) 12.0
 
March 22, 2019, 5 a.m. 8.6 ppb (8) 0.2 ppb (0) N/A 8.0 ppb (7) N/A N/A 15.0 ppb (12) 0.26 ppb (3) N/A 2.6 μg/m3 (11) 12.0
 
March 22, 2019, 4 a.m. 8.6 ppb (8) 0.1 ppb (0) N/A 9.0 ppb (8) N/A N/A 20.0 ppb (15) 0.24 ppb (3) N/A -2.1 μg/m3 (0) 15.0
 
March 22, 2019, 3 a.m. 6.8 ppb (6) 0.2 ppb (0) N/A 7.0 ppb (6) N/A N/A 33.0 ppb (25) 0.18 ppb (2) N/A -1.5 μg/m3 (0) 25.0
 
March 22, 2019, 2 a.m. 3.4 ppb (3) 0.0 ppb (0) N/A 3.0 ppb (3) N/A N/A 46.0 ppb (35) 0.15 ppb (2) N/A 1.9 μg/m3 (8) 35.0
 
March 22, 2019, 1 a.m. 2.4 ppb (2) 0.0 ppb (0) N/A 2.0 ppb (2) N/A N/A 48.0 ppb (37) 0.15 ppb (2) N/A 0.4 μg/m3 (2) 37.0
 
March 22, 2019, midnight 2.8 ppb (3) 0.5 ppb (0) N/A 2.0 ppb (2) N/A N/A 47.0 ppb (36) 0.16 ppb (2) N/A -1.0 μg/m3 (0) 36.0
 
March 21, 2019, 11 p.m. 5.0 ppb (5) 1.0 ppb (1) N/A 4.0 ppb (4) N/A N/A 46.0 ppb (35) 0.17 ppb (2) N/A -0.1 μg/m3 (0) 35.0
 
March 21, 2019, 10 p.m. 3.2 ppb (3) 0.5 ppb (0) N/A 3.0 ppb (3) N/A N/A 47.0 ppb (36) 0.17 ppb (2) N/A 2.1 μg/m3 (9) 36.0
 
March 21, 2019, 9 p.m. 3.7 ppb (3) 0.9 ppb (1) N/A 3.0 ppb (3) N/A N/A 45.0 ppb (35) 0.18 ppb (2) N/A 1.2 μg/m3 (5) 35.0
 
March 21, 2019, 8 p.m. 3.1 ppb (3) 0.7 ppb (1) N/A 2.0 ppb (2) N/A N/A 45.0 ppb (35) 0.16 ppb (2) N/A 0.5 μg/m3 (2) 35.0
 
March 21, 2019, 7 p.m. 5.1 ppb (5) 1.4 ppb (1) N/A 4.0 ppb (4) N/A N/A 42.0 ppb (32) 0.16 ppb (2) N/A -0.3 μg/m3 (0) 32.0
 
March 21, 2019, 6 p.m. 11.4 ppb (11) 2.9 ppb (3) N/A 9.0 ppb (8) N/A N/A 34.0 ppb (26) 0.21 ppb (2) N/A 0.2 μg/m3 (1) 26.0
 
March 21, 2019, 5 p.m. 10.9 ppb (10) 2.0 ppb (2) N/A 9.0 ppb (8) N/A N/A 35.0 ppb (27) 0.24 ppb (3) N/A 3.4 μg/m3 (14) 27.0
 
March 21, 2019, 4 p.m. 10.1 ppb (9) 2.0 ppb (2) N/A 8.0 ppb (7) N/A N/A 33.0 ppb (25) 0.23 ppb (3) N/A 1.2 μg/m3 (5) 25.0
 
March 21, 2019, 3 p.m. 11.7 ppb (11) 2.0 ppb (2) N/A 10.0 ppb (9) N/A N/A 31.0 ppb (24) 0.25 ppb (3) N/A 2.0 μg/m3 (8) 24.0
 
March 21, 2019, 2 p.m. 14.7 ppb (14) 2.7 ppb (3) N/A 12.0 ppb (11) N/A N/A 26.0 ppb (20) 0.25 ppb (3) N/A 9.7 μg/m3 (40) 40.0
 
March 21, 2019, 1 p.m. 35.6 ppb (33) 17.8 ppb (16) N/A 18.0 ppb (17) N/A N/A 3.0 ppb (2) 0.5 ppb (6) N/A 6.8 μg/m3 (28) 33.0
 
March 21, 2019, noon 17.3 ppb (16) 3.9 ppb (4) N/A 13.0 ppb (12) N/A N/A 2.0 ppb (2) 0.34 ppb (4) N/A 2.9 μg/m3 (12) 16.0
 
March 21, 2019, 11 a.m. 10.4 ppb (10) 0.4 ppb (0) N/A 10.0 ppb (9) N/A N/A 5.0 ppb (4) 0.32 ppb (4) N/A 9.0 μg/m3 (38) 38.0
 
March 21, 2019, 10 a.m. 11.3 ppb (10) 0.6 ppb (1) N/A 11.0 ppb (10) N/A N/A 6.0 ppb (5) 0.34 ppb (4) N/A 12.9 μg/m3 (52) 52.0
 
March 21, 2019, 9 a.m. 11.2 ppb (10) 0.1 ppb (0) N/A 11.0 ppb (10) N/A N/A 5.0 ppb (4) 0.34 ppb (4) N/A 3.6 μg/m3 (15) 15.0
 
March 21, 2019, 8 a.m. 12.9 ppb (12) 0.7 ppb (1) N/A 12.0 ppb (11) N/A N/A 4.0 ppb (3) 0.37 ppb (4) N/A -0.5 μg/m3 (0) 12.0
 
March 21, 2019, 7 a.m. 13.8 ppb (13) 0.8 ppb (1) N/A 13.0 ppb (12) N/A N/A 7.0 ppb (5) 0.36 ppb (4) N/A 5.0 μg/m3 (21) 21.0
 
March 21, 2019, 6 a.m. 11.4 ppb (11) 0.3 ppb (0) N/A 11.0 ppb (10) N/A N/A 10.0 ppb (8) 0.3 ppb (3) N/A 4.1 μg/m3 (17) 17.0
 
March 21, 2019, 5 a.m. 12.0 ppb (11) 0.4 ppb (0) N/A 12.0 ppb (11) N/A N/A 12.0 ppb (9) 0.35 ppb (4) N/A 16.3 μg/m3 (59) 59.0
 
March 21, 2019, 4 a.m. 9.6 ppb (9) -0.2 ppb (0) N/A 10.0 ppb (9) N/A N/A 12.0 ppb (9) 0.31 ppb (3) N/A 1.2 μg/m3 (5) 9.0
 
March 21, 2019, 3 a.m. 10.6 ppb (10) -0.3 ppb (0) N/A 11.0 ppb (10) N/A N/A 22.0 ppb (17) 0.25 ppb (3) N/A 1.9 μg/m3 (8) 17.0
 
March 21, 2019, 2 a.m. 3.5 ppb (3) -0.4 ppb (0) N/A 4.0 ppb (4) N/A N/A 35.0 ppb (27) 0.17 ppb (2) N/A 4.1 μg/m3 (17) 27.0
 
March 21, 2019, 1 a.m. 5.5 ppb (5) -0.3 ppb (0) N/A 6.0 ppb (6) N/A N/A 37.0 ppb (28) 0.19 ppb (2) N/A 2.8 μg/m3 (12) 28.0
 
March 21, 2019, midnight 7.7 ppb (7) -0.2 ppb (0) N/A 8.0 ppb (7) N/A N/A 38.0 ppb (29) 0.2 ppb (2) N/A -0.3 μg/m3 (0) 29.0
 
March 20, 2019, 11 p.m. 8.9 ppb (8) 0.0 ppb (0) N/A 9.0 ppb (8) N/A N/A 34.0 ppb (26) 0.21 ppb (2) N/A 0.7 μg/m3 (3) 26.0
 
March 20, 2019, 10 p.m. 8.1 ppb (8) -0.1 ppb (0) N/A 8.0 ppb (7) N/A N/A 39.0 ppb (30) 0.17 ppb (2) N/A 0.7 μg/m3 (3) 30.0
 
March 20, 2019, 9 p.m. 9.6 ppb (9) 0.2 ppb (0) N/A 9.0 ppb (8) N/A N/A 40.0 ppb (31) 0.16 ppb (2) N/A 2.6 μg/m3 (11) 31.0
 
March 20, 2019, 8 p.m. 8.9 ppb (8) 0.6 ppb (1) N/A 8.0 ppb (7) N/A N/A 42.0 ppb (32) 0.18 ppb (2) N/A 5.0 μg/m3 (21) 32.0
 
March 20, 2019, 7 p.m. 7.9 ppb (7) 1.5 ppb (1) N/A 6.0 ppb (6) N/A N/A 44.0 ppb (34) 0.17 ppb (2) N/A 2.1 μg/m3 (9) 34.0
 
March 20, 2019, 6 p.m. 6.3 ppb (6) 1.4 ppb (1) N/A 5.0 ppb (5) N/A N/A 46.0 ppb (35) 0.17 ppb (2) N/A 2.6 μg/m3 (11) 35.0
 
March 20, 2019, 5 p.m. 7.5 ppb (7) 1.6 ppb (1) N/A 6.0 ppb (6) N/A N/A 43.0 ppb (33) 0.17 ppb (2) N/A 7.7 μg/m3 (32) 33.0
 
March 20, 2019, 4 p.m. 12.7 ppb (12) 2.4 ppb (2) N/A 10.0 ppb (9) N/A N/A 33.0 ppb (25) 0.19 ppb (2) N/A 8.7 μg/m3 (36) 36.0
 
March 20, 2019, 3 p.m. 18.5 ppb (17) 2.4 ppb (2) N/A 16.0 ppb (15) N/A N/A 23.0 ppb (18) 0.22 ppb (2) N/A 6.5 μg/m3 (27) 27.0
 
March 20, 2019, 2 p.m. 22.1 ppb (20) 1.5 ppb (1) N/A 21.0 ppb (19) N/A N/A 19.0 ppb (15) 0.26 ppb (3) N/A 4.8 μg/m3 (20) 20.0
 
March 20, 2019, 1 p.m. 11.9 ppb (11) 0.7 ppb (1) N/A 11.0 ppb (10) N/A N/A 29.0 ppb (22) 0.23 ppb (3) N/A 5.5 μg/m3 (23) 23.0
 
March 20, 2019, noon 5.8 ppb (5) 0.0 ppb (0) N/A 6.0 ppb (6) N/A N/A 37.0 ppb (28) 0.18 ppb (2) N/A 5.8 μg/m3 (24) 28.0
 
March 20, 2019, 11 a.m. 3.4 ppb (3) -0.5 ppb (0) N/A 4.0 ppb (4) N/A N/A 40.0 ppb (31) 0.15 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 20, 2019, 10 a.m. 3.0 ppb (3) 0.0 ppb (0) N/A 3.0 ppb (3) N/A N/A 42.0 ppb (32) 0.16 ppb (2) N/A 7.0 μg/m3 (29) 32.0
 
March 20, 2019, 9 a.m. 1.0 ppb (1) -0.4 ppb (0) N/A 1.0 ppb (1) N/A N/A 45.0 ppb (35) 0.13 ppb (1) N/A 4.6 μg/m3 (19) 35.0
 
March 20, 2019, 8 a.m. 1.7 ppb (2) -0.3 ppb (0) N/A 2.0 ppb (2) N/A N/A 44.0 ppb (34) 0.14 ppb (2) N/A 4.5 μg/m3 (19) 34.0
 
March 20, 2019, 7 a.m. 4.6 ppb (4) -0.1 ppb (0) N/A 5.0 ppb (5) N/A N/A 41.0 ppb (32) 0.13 ppb (1) N/A 5.5 μg/m3 (23) 32.0
 
March 20, 2019, 6 a.m. 4.4 ppb (4) -0.1 ppb (0) N/A 5.0 ppb (5) N/A N/A 40.0 ppb (31) 0.15 ppb (2) N/A 10.0 μg/m3 (42) 42.0
 
March 20, 2019, 5 a.m. 7.0 ppb (6) 0.0 ppb (0) N/A 7.0 ppb (6) N/A N/A 38.0 ppb (29) 0.12 ppb (1) N/A 8.7 μg/m3 (36) 36.0
 
March 20, 2019, 4 a.m. 9.2 ppb (9) 1.7 ppb (2) N/A 7.0 ppb (6) N/A N/A 41.0 ppb (32) 0.14 ppb (2) N/A 3.6 μg/m3 (15) 32.0
 
March 20, 2019, 3 a.m. 9.0 ppb (8) 0.0 ppb (0) N/A 9.0 ppb (8) N/A N/A 38.0 ppb (29) 0.19 ppb (2) N/A 15.6 μg/m3 (58) 58.0
 
March 20, 2019, 2 a.m. 13.1 ppb (12) 0.1 ppb (0) N/A 13.0 ppb (12) N/A N/A 38.0 ppb (29) 0.2 ppb (2) N/A 8.9 μg/m3 (37) 37.0
 
March 20, 2019, 1 a.m. 13.8 ppb (13) 0.4 ppb (0) N/A 13.0 ppb (12) N/A N/A 40.0 ppb (31) 0.21 ppb (2) N/A 7.5 μg/m3 (31) 31.0
 
March 20, 2019, midnight 13.0 ppb (12) 0.9 ppb (1) N/A 12.0 ppb (11) N/A N/A 47.0 ppb (36) 0.24 ppb (3) N/A 11.0 μg/m3 (46) 46.0
 
March 19, 2019, 11 p.m. 14.8 ppb (14) 2.1 ppb (2) N/A 13.0 ppb (12) N/A N/A 51.0 ppb (39) 0.24 ppb (3) N/A 13.6 μg/m3 (53) 53.0
 
March 19, 2019, 10 p.m. 17.3 ppb (16) 2.3 ppb (2) N/A 15.0 ppb (14) N/A N/A 50.0 ppb (38) 0.24 ppb (3) N/A 18.7 μg/m3 (64) 64.0
 
March 19, 2019, 9 p.m. 20.7 ppb (19) 3.5 ppb (3) N/A 17.0 ppb (16) N/A N/A 50.0 ppb (38) 0.32 ppb (4) N/A 21.0 μg/m3 (69) 69.0
 
March 19, 2019, 8 p.m. 27.9 ppb (26) 5.4 ppb (5) N/A 22.0 ppb (20) N/A N/A 46.0 ppb (35) 0.46 ppb (5) N/A 18.5 μg/m3 (64) 64.0
 
March 19, 2019, 7 p.m. 25.4 ppb (24) 5.1 ppb (5) N/A 20.0 ppb (19) N/A N/A 44.0 ppb (34) 0.44 ppb (5) N/A 16.5 μg/m3 (60) 60.0
 
March 19, 2019, 6 p.m. 25.0 ppb (23) 6.7 ppb (6) N/A 18.0 ppb (17) N/A N/A 38.0 ppb (29) 0.35 ppb (4) N/A 8.0 μg/m3 (33) 33.0
 
March 19, 2019, 5 p.m. 23.7 ppb (22) 7.2 ppb (7) N/A 17.0 ppb (16) N/A N/A 25.0 ppb (19) 0.32 ppb (4) N/A 2.3 μg/m3 (10) 22.0
 
March 19, 2019, 4 p.m. 36.6 ppb (34) 14.7 ppb (14) N/A 22.0 ppb (20) N/A N/A 17.0 ppb (13) 0.43 ppb (5) N/A 7.0 μg/m3 (29) 34.0
 
March 19, 2019, 3 p.m. 45.8 ppb (42) 22.7 ppb (21) N/A 23.0 ppb (21) N/A N/A 10.0 ppb (8) 0.52 ppb (6) N/A 9.5 μg/m3 (40) 42.0
 
March 19, 2019, 2 p.m. 51.7 ppb (48) 28.4 ppb (26) N/A 23.0 ppb (21) N/A N/A 4.0 ppb (3) 0.65 ppb (7) N/A 7.2 μg/m3 (30) 48.0
 
March 19, 2019, 1 p.m. 27.3 ppb (25) 8.5 ppb (8) N/A 19.0 ppb (18) N/A N/A 4.0 ppb (3) 0.4 ppb (4) N/A 9.7 μg/m3 (40) 40.0
 
March 19, 2019, noon 14.9 ppb (14) 1.4 ppb (1) N/A 13.0 ppb (12) N/A N/A 8.0 ppb (6) 0.31 ppb (3) N/A 8.5 μg/m3 (35) 35.0
 
March 19, 2019, 11 a.m. 8.7 ppb (8) -0.2 ppb (0) N/A 9.0 ppb (8) N/A N/A 15.0 ppb (12) 0.26 ppb (3) N/A 4.5 μg/m3 (19) 19.0
 
March 19, 2019, 10 a.m. 13.0 ppb (12) 0.2 ppb (0) N/A 13.0 ppb (12) N/A N/A 15.0 ppb (12) 0.29 ppb (3) N/A 3.8 μg/m3 (16) 16.0
 
March 19, 2019, 9 a.m. 9.9 ppb (9) -0.3 ppb (0) N/A 10.0 ppb (9) N/A N/A 20.0 ppb (15) 0.28 ppb (3) N/A 7.2 μg/m3 (30) 30.0
 
March 19, 2019, 8 a.m. 11.6 ppb (11) -0.2 ppb (0) N/A 12.0 ppb (11) N/A N/A 21.0 ppb (16) 0.31 ppb (3) N/A 9.4 μg/m3 (39) 39.0
 
March 19, 2019, 7 a.m. 11.9 ppb (11) -0.2 ppb (0) N/A 12.0 ppb (11) N/A N/A 23.0 ppb (18) 0.32 ppb (4) N/A 8.5 μg/m3 (35) 35.0
 
March 19, 2019, 6 a.m. 12.3 ppb (11) -0.2 ppb (0) N/A 13.0 ppb (12) N/A N/A 26.0 ppb (20) 0.35 ppb (4) N/A 8.7 μg/m3 (36) 36.0
 
March 19, 2019, 5 a.m. 11.1 ppb (10) -0.4 ppb (0) N/A 11.0 ppb (10) N/A N/A 31.0 ppb (24) 0.31 ppb (3) N/A 10.2 μg/m3 (42) 42.0
 
March 19, 2019, 4 a.m. 19.2 ppb (18) -0.1 ppb (0) N/A 19.0 ppb (18) N/A N/A 35.0 ppb (27) 0.38 ppb (4) N/A 11.2 μg/m3 (47) 47.0
 
March 19, 2019, 3 a.m. 24.6 ppb (23) -0.1 ppb (0) N/A 25.0 ppb (23) N/A N/A 36.0 ppb (28) 0.41 ppb (5) N/A 7.5 μg/m3 (31) 31.0
 
March 19, 2019, 2 a.m. 8.8 ppb (8) -0.2 ppb (0) N/A 9.0 ppb (8) N/A N/A 51.0 ppb (39) 0.23 ppb (3) N/A 3.8 μg/m3 (16) 39.0
 
March 19, 2019, 1 a.m. 5.6 ppb (5) -0.1 ppb (0) N/A 6.0 ppb (6) N/A N/A 64.0 ppb (49) 0.22 ppb (2) N/A 3.1 μg/m3 (13) 49.0
 
March 19, 2019, midnight 3.7 ppb (3) -0.1 ppb (0) N/A 4.0 ppb (4) N/A N/A 62.0 ppb (48) 0.19 ppb (2) N/A 2.6 μg/m3 (11) 48.0
 
March 18, 2019, 11 p.m. 1.7 ppb (2) -0.1 ppb (0) N/A 2.0 ppb (2) N/A N/A 57.0 ppb (44) 0.15 ppb (2) N/A -0.3 μg/m3 (0) 44.0
 
March 18, 2019, 10 p.m. 2.3 ppb (2) 0.0 ppb (0) N/A 2.0 ppb (2) N/A N/A 57.0 ppb (44) 0.15 ppb (2) N/A 2.3 μg/m3 (10) 44.0
 
March 18, 2019, 9 p.m. 5.1 ppb (5) 0.6 ppb (1) N/A 5.0 ppb (5) N/A N/A 63.0 ppb (48) 0.19 ppb (2) N/A 3.3 μg/m3 (14) 48.0
 
March 18, 2019, 8 p.m. 5.9 ppb (5) 0.6 ppb (1) N/A 5.0 ppb (5) N/A N/A 60.0 ppb (46) 0.19 ppb (2) N/A 1.8 μg/m3 (8) 46.0
 
March 18, 2019, 7 p.m. 6.9 ppb (6) 0.7 ppb (1) N/A 6.0 ppb (6) N/A N/A 59.0 ppb (45) 0.2 ppb (2) N/A 3.1 μg/m3 (13) 45.0
 
March 18, 2019, 6 p.m. 9.1 ppb (8) 1.8 ppb (2) N/A 7.0 ppb (6) N/A N/A 48.0 ppb (37) 0.21 ppb (2) N/A 0.5 μg/m3 (2) 37.0
 
March 18, 2019, 5 p.m. 12.3 ppb (11) 3.7 ppb (3) N/A 9.0 ppb (8) N/A N/A 38.0 ppb (29) 0.2 ppb (2) N/A 2.6 μg/m3 (11) 29.0
 
March 18, 2019, 4 p.m. 36.7 ppb (34) 16.5 ppb (15) N/A 20.0 ppb (19) N/A N/A 19.0 ppb (15) 0.38 ppb (4) N/A 7.0 μg/m3 (29) 34.0
 
March 18, 2019, 3 p.m. 41.9 ppb (39) 21.4 ppb (20) N/A 20.0 ppb (19) N/A N/A 10.0 ppb (8) 0.51 ppb (6) N/A 9.7 μg/m3 (40) 40.0
 
March 18, 2019, 2 p.m. 51.7 ppb (48) 30.0 ppb (28) N/A 22.0 ppb (20) N/A N/A 4.0 ppb (3) 0.59 ppb (7) N/A 9.7 μg/m3 (40) 48.0
 
March 18, 2019, 1 p.m. 35.5 ppb (33) 15.1 ppb (14) N/A 20.0 ppb (19) N/A N/A 4.0 ppb (3) 0.53 ppb (6) N/A 5.8 μg/m3 (24) 33.0
 
March 18, 2019, noon 21.8 ppb (20) 3.4 ppb (3) N/A 18.0 ppb (17) N/A N/A 5.0 ppb (4) 0.55 ppb (6) N/A 1.6 μg/m3 (7) 20.0
 
March 18, 2019, 11 a.m. 7.5 ppb (7) 0.1 ppb (0) N/A 7.0 ppb (6) N/A N/A 16.0 ppb (12) 0.22 ppb (2) N/A -2.7 μg/m3 (0) 12.0
 
March 18, 2019, 10 a.m. 7.0 ppb (6) 0.6 ppb (1) N/A 6.0 ppb (6) N/A N/A 15.0 ppb (12) 0.21 ppb (2) N/A -0.3 μg/m3 (0) 12.0
 
March 18, 2019, 9 a.m. 5.8 ppb (5) -0.1 ppb (0) N/A 6.0 ppb (6) N/A N/A 18.0 ppb (14) 0.2 ppb (2) N/A 7.5 μg/m3 (31) 31.0