Howard Co MD, US: 39.143197, -76.846192
| Date Observed (UTC) | NOX | NO | NOY | NO2 | NO2Y | SO2 | OZONE | CO | PM10 | PM2.5 | AQI | AQI/500 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| March 20, 2019, 11 p.m. | 37.1 ppb (34) | 10.8 ppb (10) | N/A | 26.0 ppb (24) | N/A | N/A | N/A | 0.32 ppb (4) | N/A | 7.0 μg/m3 (29) | 34.0 | |
| March 20, 2019, 10 p.m. | 35.2 ppb (33) | 11.5 ppb (11) | N/A | 24.0 ppb (22) | N/A | N/A | N/A | 0.3 ppb (3) | N/A | 11.0 μg/m3 (46) | 46.0 | |
| March 20, 2019, 9 p.m. | 32.0 ppb (30) | 10.0 ppb (9) | N/A | 22.0 ppb (20) | N/A | N/A | N/A | 0.3 ppb (3) | N/A | 5.0 μg/m3 (21) | 30.0 | |
| March 20, 2019, 8 p.m. | 37.1 ppb (34) | 12.6 ppb (12) | N/A | 25.0 ppb (23) | N/A | N/A | N/A | 0.29 ppb (3) | N/A | 5.0 μg/m3 (21) | 34.0 | |
| March 20, 2019, 7 p.m. | 37.1 ppb (34) | 12.0 ppb (11) | N/A | 25.0 ppb (23) | N/A | N/A | N/A | 0.3 ppb (3) | N/A | 3.0 μg/m3 (12) | 34.0 | |
| March 20, 2019, 6 p.m. | 44.4 ppb (41) | 14.6 ppb (14) | N/A | 30.0 ppb (28) | N/A | N/A | N/A | 0.26 ppb (3) | N/A | 5.0 μg/m3 (21) | 41.0 | |
| March 20, 2019, 5 p.m. | 40.7 ppb (38) | 16.5 ppb (15) | N/A | 24.0 ppb (22) | N/A | N/A | N/A | 0.24 ppb (3) | N/A | 9.0 μg/m3 (38) | 38.0 | |
| March 20, 2019, 4 p.m. | 49.2 ppb (46) | 22.1 ppb (20) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.28 ppb (3) | N/A | 7.0 μg/m3 (29) | 46.0 | |
| March 20, 2019, 3 p.m. | 55.5 ppb (52) | 29.6 ppb (27) | N/A | 26.0 ppb (24) | N/A | N/A | N/A | 0.34 ppb (4) | N/A | 7.0 μg/m3 (29) | 52.0 | |
| March 20, 2019, 2 p.m. | 64.8 ppb (61) | 36.8 ppb (34) | N/A | 28.0 ppb (26) | N/A | N/A | N/A | 0.41 ppb (5) | N/A | 9.0 μg/m3 (38) | 61.0 | |
| March 20, 2019, 1 p.m. | 82.8 ppb (81) | 55.3 ppb (51) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.52 ppb (6) | N/A | 12.0 μg/m3 (50) | 81.0 | |
| March 20, 2019, noon | 75.1 ppb (72) | 48.6 ppb (45) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.49 ppb (5) | N/A | 10.0 μg/m3 (42) | 72.0 | |
| March 20, 2019, 11 a.m. | 53.5 ppb (50) | 29.1 ppb (27) | N/A | 24.0 ppb (22) | N/A | N/A | N/A | 0.34 ppb (4) | N/A | 9.0 μg/m3 (38) | 50.0 | |
| March 20, 2019, 10 a.m. | 45.6 ppb (42) | 22.3 ppb (21) | N/A | 23.0 ppb (21) | N/A | N/A | N/A | 0.3 ppb (3) | N/A | 8.0 μg/m3 (33) | 42.0 | |
| March 20, 2019, 9 a.m. | 75.4 ppb (73) | 48.5 ppb (45) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.32 ppb (4) | N/A | 5.0 μg/m3 (21) | 73.0 | |
| March 20, 2019, 8 a.m. | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 0.27 ppb (3) | N/A | 7.0 μg/m3 (29) | 29.0 | |
| March 20, 2019, 7 a.m. | 68.4 ppb (65) | 40.9 ppb (38) | N/A | 28.0 ppb (26) | N/A | N/A | N/A | 0.31 ppb (3) | N/A | 6.0 μg/m3 (25) | 65.0 | |
| March 20, 2019, 6 a.m. | 27.8 ppb (26) | 9.5 ppb (9) | N/A | 18.0 ppb (17) | N/A | N/A | N/A | 0.21 ppb (2) | N/A | 5.0 μg/m3 (21) | 26.0 | |
| March 20, 2019, 5 a.m. | 31.0 ppb (29) | 10.9 ppb (10) | N/A | 20.0 ppb (19) | N/A | N/A | N/A | 0.23 ppb (3) | N/A | 4.0 μg/m3 (17) | 29.0 | |
| March 20, 2019, 4 a.m. | 27.0 ppb (25) | 6.8 ppb (6) | N/A | 20.0 ppb (19) | N/A | N/A | N/A | 0.24 ppb (3) | N/A | 1.0 μg/m3 (4) | 25.0 | |
| March 20, 2019, 3 a.m. | 25.2 ppb (23) | 6.2 ppb (6) | N/A | 19.0 ppb (18) | N/A | N/A | N/A | 0.27 ppb (3) | N/A | 1.0 μg/m3 (4) | 23.0 | |
| March 20, 2019, 2 a.m. | 24.0 ppb (22) | 2.8 ppb (3) | N/A | 21.0 ppb (19) | N/A | N/A | N/A | 0.28 ppb (3) | N/A | 3.0 μg/m3 (12) | 22.0 | |
| March 20, 2019, 1 a.m. | 31.8 ppb (29) | 7.3 ppb (7) | N/A | 25.0 ppb (23) | N/A | N/A | N/A | 0.32 ppb (4) | N/A | 6.0 μg/m3 (25) | 29.0 | |
| March 20, 2019, midnight | 39.9 ppb (37) | 12.8 ppb (12) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.31 ppb (3) | N/A | 8.0 μg/m3 (33) | 37.0 | |
| March 19, 2019, 11 p.m. | 20.4 ppb (19) | 6.2 ppb (6) | N/A | 14.0 ppb (13) | N/A | N/A | N/A | 0.26 ppb (3) | N/A | 9.0 μg/m3 (38) | 38.0 | |
| March 19, 2019, 10 p.m. | 10.4 ppb (10) | 1.9 ppb (2) | N/A | 8.0 ppb (7) | N/A | N/A | N/A | 0.22 ppb (2) | N/A | 6.0 μg/m3 (25) | 25.0 | |
| March 19, 2019, 9 p.m. | 9.7 ppb (9) | 1.1 ppb (1) | N/A | 9.0 ppb (8) | N/A | N/A | N/A | 0.21 ppb (2) | N/A | 3.0 μg/m3 (12) | 12.0 | |
| March 19, 2019, 8 p.m. | 15.7 ppb (15) | 5.0 ppb (5) | N/A | 11.0 ppb (10) | N/A | N/A | N/A | 0.23 ppb (3) | N/A | 0.0 μg/m3 (0) | 15.0 | |
| March 19, 2019, 7 p.m. | 11.0 ppb (10) | 1.3 ppb (1) | N/A | 10.0 ppb (9) | N/A | N/A | N/A | 0.21 ppb (2) | N/A | -2.0 μg/m3 (0) | 10.0 | |
| March 19, 2019, 6 p.m. | 18.5 ppb (17) | 4.0 ppb (4) | N/A | 14.0 ppb (13) | N/A | N/A | N/A | 0.23 ppb (3) | N/A | 2.0 μg/m3 (8) | 17.0 | |
| March 19, 2019, 5 p.m. | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 0.26 ppb (3) | N/A | 4.0 μg/m3 (17) | 17.0 | |
| March 19, 2019, 4 p.m. | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 0.26 ppb (3) | N/A | 3.0 μg/m3 (12) | 12.0 | |
| March 19, 2019, 3 p.m. | 44.3 ppb (41) | 17.3 ppb (16) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.29 ppb (3) | N/A | N/A | 41.0 | |
| March 19, 2019, 2 p.m. | 34.6 ppb (32) | 14.8 ppb (14) | N/A | 20.0 ppb (19) | N/A | N/A | N/A | 0.27 ppb (3) | N/A | 8.0 μg/m3 (33) | 33.0 | |
| March 19, 2019, 1 p.m. | 37.5 ppb (35) | 17.5 ppb (16) | N/A | 20.0 ppb (19) | N/A | N/A | N/A | 0.31 ppb (3) | N/A | 8.0 μg/m3 (33) | 35.0 | |
| March 19, 2019, noon | 67.8 ppb (65) | 43.2 ppb (40) | N/A | 25.0 ppb (23) | N/A | N/A | N/A | 0.37 ppb (4) | N/A | 9.0 μg/m3 (38) | 65.0 | |
| March 19, 2019, 11 a.m. | 94.7 ppb (93) | 65.6 ppb (62) | N/A | 29.0 ppb (27) | N/A | N/A | N/A | 0.34 ppb (4) | N/A | 7.0 μg/m3 (29) | 93.0 | |
| March 19, 2019, 10 a.m. | 52.7 ppb (49) | 29.4 ppb (27) | N/A | 23.0 ppb (21) | N/A | N/A | N/A | 0.27 ppb (3) | N/A | 8.0 μg/m3 (33) | 49.0 | |
| March 19, 2019, 9 a.m. | 41.0 ppb (38) | 21.3 ppb (20) | N/A | 20.0 ppb (19) | N/A | N/A | N/A | 0.24 ppb (3) | N/A | 12.0 μg/m3 (50) | 50.0 | |
| March 19, 2019, 8 a.m. | 37.0 ppb (34) | 18.1 ppb (17) | N/A | 19.0 ppb (18) | N/A | N/A | N/A | 0.23 ppb (3) | N/A | 7.0 μg/m3 (29) | 34.0 | |
| March 19, 2019, 7 a.m. | 35.0 ppb (32) | 15.4 ppb (14) | N/A | 20.0 ppb (19) | N/A | N/A | N/A | N/A | N/A | 6.0 μg/m3 (25) | 32.0 | |
| March 19, 2019, 6 a.m. | 51.7 ppb (48) | 26.4 ppb (24) | N/A | 25.0 ppb (23) | N/A | N/A | N/A | 0.23 ppb (3) | N/A | 10.0 μg/m3 (42) | 48.0 | |
| March 19, 2019, 5 a.m. | 47.0 ppb (44) | 24.4 ppb (23) | N/A | 23.0 ppb (21) | N/A | N/A | N/A | 0.24 ppb (3) | N/A | 10.0 μg/m3 (42) | 44.0 | |
| March 19, 2019, 4 a.m. | 23.9 ppb (22) | 5.6 ppb (5) | N/A | 18.0 ppb (17) | N/A | N/A | N/A | N/A | N/A | 10.0 μg/m3 (42) | 42.0 | |
| March 19, 2019, 3 a.m. | 42.3 ppb (39) | 14.2 ppb (13) | N/A | 28.0 ppb (26) | N/A | N/A | N/A | 0.21 ppb (2) | N/A | 9.0 μg/m3 (38) | 39.0 | |
| March 19, 2019, 2 a.m. | 45.7 ppb (42) | 13.7 ppb (13) | N/A | 32.0 ppb (30) | N/A | N/A | N/A | 0.24 ppb (3) | N/A | 7.0 μg/m3 (29) | 42.0 | |
| March 19, 2019, 1 a.m. | 47.8 ppb (44) | 16.1 ppb (15) | N/A | 32.0 ppb (30) | N/A | N/A | N/A | 0.27 ppb (3) | N/A | 8.0 μg/m3 (33) | 44.0 | |
| March 19, 2019, midnight | 40.6 ppb (38) | 13.4 ppb (12) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.28 ppb (3) | N/A | 6.0 μg/m3 (25) | 38.0 | |
| March 18, 2019, 11 p.m. | 33.5 ppb (31) | 11.0 ppb (10) | N/A | 22.0 ppb (20) | N/A | N/A | N/A | 0.27 ppb (3) | N/A | 9.0 μg/m3 (38) | 38.0 | |
| March 18, 2019, 10 p.m. | 18.8 ppb (17) | 4.0 ppb (4) | N/A | 15.0 ppb (14) | N/A | N/A | N/A | 0.18 ppb (2) | N/A | 9.0 μg/m3 (38) | 38.0 | |
| March 18, 2019, 9 p.m. | 21.6 ppb (20) | 5.6 ppb (5) | N/A | 16.0 ppb (15) | N/A | N/A | N/A | 0.19 ppb (2) | N/A | 7.0 μg/m3 (29) | 29.0 | |
| March 18, 2019, 8 p.m. | 20.4 ppb (19) | 4.8 ppb (4) | N/A | 16.0 ppb (15) | N/A | N/A | N/A | 0.21 ppb (2) | N/A | 8.0 μg/m3 (33) | 33.0 | |
| March 18, 2019, 7 p.m. | 25.6 ppb (24) | 7.9 ppb (7) | N/A | 18.0 ppb (17) | N/A | N/A | N/A | 0.23 ppb (3) | N/A | 7.0 μg/m3 (29) | 29.0 | |
| March 18, 2019, 6 p.m. | 28.1 ppb (26) | 10.3 ppb (10) | N/A | 18.0 ppb (17) | N/A | N/A | N/A | 0.23 ppb (3) | N/A | 6.0 μg/m3 (25) | 26.0 | |
| March 18, 2019, 5 p.m. | 37.2 ppb (34) | 16.3 ppb (15) | N/A | 21.0 ppb (19) | N/A | N/A | N/A | 0.25 ppb (3) | N/A | 6.0 μg/m3 (25) | 34.0 | |
| March 18, 2019, 4 p.m. | 41.0 ppb (38) | 19.2 ppb (18) | N/A | 22.0 ppb (20) | N/A | N/A | N/A | 0.26 ppb (3) | N/A | 5.0 μg/m3 (21) | 38.0 | |
| March 18, 2019, 3 p.m. | 44.3 ppb (41) | 21.7 ppb (20) | N/A | 23.0 ppb (21) | N/A | N/A | N/A | 0.27 ppb (3) | N/A | 7.0 μg/m3 (29) | 41.0 | |
| March 18, 2019, 2 p.m. | 44.4 ppb (41) | 19.9 ppb (18) | N/A | 25.0 ppb (23) | N/A | N/A | N/A | 0.26 ppb (3) | N/A | 8.0 μg/m3 (33) | 41.0 | |
| March 18, 2019, 1 p.m. | 56.2 ppb (52) | 27.4 ppb (25) | N/A | 29.0 ppb (27) | N/A | N/A | N/A | 0.29 ppb (3) | N/A | 7.0 μg/m3 (29) | 52.0 | |
| March 18, 2019, noon | 77.8 ppb (75) | 43.4 ppb (40) | N/A | 34.0 ppb (31) | N/A | N/A | N/A | 0.43 ppb (5) | N/A | 12.0 μg/m3 (50) | 75.0 | |
| March 18, 2019, 11 a.m. | 53.8 ppb (50) | 24.0 ppb (22) | N/A | 30.0 ppb (28) | N/A | N/A | N/A | 0.32 ppb (4) | N/A | 4.0 μg/m3 (17) | 50.0 | |
| March 18, 2019, 10 a.m. | 40.8 ppb (38) | 14.2 ppb (13) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.24 ppb (3) | N/A | 6.0 μg/m3 (25) | 38.0 | |
| March 18, 2019, 9 a.m. | 40.3 ppb (37) | 13.2 ppb (12) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.25 ppb (3) | N/A | 5.0 μg/m3 (21) | 37.0 | |
| March 18, 2019, 8 a.m. | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 0.26 ppb (3) | N/A | 7.0 μg/m3 (29) | 29.0 | |
| March 18, 2019, 7 a.m. | 38.3 ppb (35) | 11.4 ppb (11) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.24 ppb (3) | N/A | 6.0 μg/m3 (25) | 35.0 | |
| March 18, 2019, 6 a.m. | 36.2 ppb (34) | 11.3 ppb (10) | N/A | 25.0 ppb (23) | N/A | N/A | N/A | 0.26 ppb (3) | N/A | 4.0 μg/m3 (17) | 34.0 | |
| March 18, 2019, 5 a.m. | 38.3 ppb (35) | 12.3 ppb (11) | N/A | 26.0 ppb (24) | N/A | N/A | N/A | 0.29 ppb (3) | N/A | 6.0 μg/m3 (25) | 35.0 | |
| March 18, 2019, 4 a.m. | 23.8 ppb (22) | 7.7 ppb (7) | N/A | 16.0 ppb (15) | N/A | N/A | N/A | 0.27 ppb (3) | N/A | 6.0 μg/m3 (25) | 25.0 | |
| March 18, 2019, 3 a.m. | 18.3 ppb (17) | 2.0 ppb (2) | N/A | 16.0 ppb (15) | N/A | N/A | N/A | 0.25 ppb (3) | N/A | 4.0 μg/m3 (17) | 17.0 | |
| March 18, 2019, 2 a.m. | 16.7 ppb (15) | 2.3 ppb (2) | N/A | 14.0 ppb (13) | N/A | N/A | N/A | 0.24 ppb (3) | N/A | 5.0 μg/m3 (21) | 21.0 | |
| March 18, 2019, 1 a.m. | 17.5 ppb (16) | 3.8 ppb (4) | N/A | 14.0 ppb (13) | N/A | N/A | N/A | 0.24 ppb (3) | N/A | 6.0 μg/m3 (25) | 25.0 | |
| March 18, 2019, midnight | 7.1 ppb (7) | 0.8 ppb (1) | N/A | 6.0 ppb (6) | N/A | N/A | N/A | 0.19 ppb (2) | N/A | 7.0 μg/m3 (29) | 29.0 | |
| March 17, 2019, 11 p.m. | 9.4 ppb (9) | 0.8 ppb (1) | N/A | 9.0 ppb (8) | N/A | N/A | N/A | 0.18 ppb (2) | N/A | 6.0 μg/m3 (25) | 25.0 | |
| March 17, 2019, 10 p.m. | 6.5 ppb (6) | 1.0 ppb (1) | N/A | 5.0 ppb (5) | N/A | N/A | N/A | 0.17 ppb (2) | N/A | 4.0 μg/m3 (17) | 17.0 | |
| March 17, 2019, 9 p.m. | 5.1 ppb (5) | 0.9 ppb (1) | N/A | 4.0 ppb (4) | N/A | N/A | N/A | 0.17 ppb (2) | N/A | 3.0 μg/m3 (12) | 12.0 | |
| March 17, 2019, 8 p.m. | 4.8 ppb (4) | 0.9 ppb (1) | N/A | 4.0 ppb (4) | N/A | N/A | N/A | 0.17 ppb (2) | N/A | 1.0 μg/m3 (4) | 4.0 | |
| March 17, 2019, 7 p.m. | 4.8 ppb (4) | 0.9 ppb (1) | N/A | 4.0 ppb (4) | N/A | N/A | N/A | 0.17 ppb (2) | N/A | 1.0 μg/m3 (4) | 4.0 | |
| March 17, 2019, 6 p.m. | 4.7 ppb (4) | 0.8 ppb (1) | N/A | 4.0 ppb (4) | N/A | N/A | N/A | 0.17 ppb (2) | N/A | 0.0 μg/m3 (0) | 4.0 | |
| March 17, 2019, 5 p.m. | 4.6 ppb (4) | 0.9 ppb (1) | N/A | 4.0 ppb (4) | N/A | N/A | N/A | 0.17 ppb (2) | N/A | -2.0 μg/m3 (0) | 4.0 | |
| March 17, 2019, 4 p.m. | 5.1 ppb (5) | 0.9 ppb (1) | N/A | 4.0 ppb (4) | N/A | N/A | N/A | 0.17 ppb (2) | N/A | -2.0 μg/m3 (0) | 5.0 | |
| March 17, 2019, 3 p.m. | 5.2 ppb (5) | 0.7 ppb (1) | N/A | 5.0 ppb (5) | N/A | N/A | N/A | 0.17 ppb (2) | N/A | 0.0 μg/m3 (0) | 5.0 | |
| March 17, 2019, 2 p.m. | 6.4 ppb (6) | 0.8 ppb (1) | N/A | 6.0 ppb (6) | N/A | N/A | N/A | 0.17 ppb (2) | N/A | -2.0 μg/m3 (0) | 6.0 | |
| March 17, 2019, 1 p.m. | 9.4 ppb (9) | 1.1 ppb (1) | N/A | 8.0 ppb (7) | N/A | N/A | N/A | 0.18 ppb (2) | N/A | 0.0 μg/m3 (0) | 9.0 | |
| March 17, 2019, noon | 23.1 ppb (21) | 6.5 ppb (6) | N/A | 17.0 ppb (16) | N/A | N/A | N/A | 0.25 ppb (3) | N/A | 3.0 μg/m3 (12) | 21.0 | |
| March 17, 2019, 11 a.m. | 28.8 ppb (27) | 9.2 ppb (9) | N/A | 20.0 ppb (19) | N/A | N/A | N/A | 0.24 ppb (3) | N/A | 3.0 μg/m3 (12) | 27.0 | |
| March 17, 2019, 10 a.m. | 20.2 ppb (19) | 4.1 ppb (4) | N/A | 16.0 ppb (15) | N/A | N/A | N/A | 0.2 ppb (2) | N/A | 3.0 μg/m3 (12) | 19.0 | |
| March 17, 2019, 9 a.m. | 21.5 ppb (20) | 4.7 ppb (4) | N/A | 17.0 ppb (16) | N/A | N/A | N/A | 0.21 ppb (2) | N/A | 2.0 μg/m3 (8) | 20.0 | |
| March 17, 2019, 8 a.m. | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 0.22 ppb (2) | N/A | 3.0 μg/m3 (12) | 12.0 | |
| March 17, 2019, 7 a.m. | 10.6 ppb (10) | 0.8 ppb (1) | N/A | 10.0 ppb (9) | N/A | N/A | N/A | 0.2 ppb (2) | N/A | 4.0 μg/m3 (17) | 17.0 | |
| March 17, 2019, 6 a.m. | 13.7 ppb (13) | 1.9 ppb (2) | N/A | 12.0 ppb (11) | N/A | N/A | N/A | 0.2 ppb (2) | N/A | 3.0 μg/m3 (12) | 13.0 | |
| March 17, 2019, 5 a.m. | 8.9 ppb (8) | 1.9 ppb (2) | N/A | 7.0 ppb (6) | N/A | N/A | N/A | 0.17 ppb (2) | N/A | 3.0 μg/m3 (12) | 12.0 | |
| March 17, 2019, 4 a.m. | 3.8 ppb (4) | 0.5 ppb (0) | N/A | 3.0 ppb (3) | N/A | N/A | N/A | 0.15 ppb (2) | N/A | 3.0 μg/m3 (12) | 12.0 | |
| March 17, 2019, 3 a.m. | 3.3 ppb (3) | 0.3 ppb (0) | N/A | 3.0 ppb (3) | N/A | N/A | N/A | 0.24 ppb (3) | N/A | 2.0 μg/m3 (8) | 8.0 | |
| March 17, 2019, 2 a.m. | 3.7 ppb (3) | 0.3 ppb (0) | N/A | 3.0 ppb (3) | N/A | N/A | N/A | 0.24 ppb (3) | N/A | 3.0 μg/m3 (12) | 12.0 | |
| March 17, 2019, 1 a.m. | 4.5 ppb (4) | 0.5 ppb (0) | N/A | 4.0 ppb (4) | N/A | N/A | N/A | 0.23 ppb (3) | N/A | 3.0 μg/m3 (12) | 12.0 | |
| March 17, 2019, midnight | 5.7 ppb (5) | 0.7 ppb (1) | N/A | 5.0 ppb (5) | N/A | N/A | N/A | 0.23 ppb (3) | N/A | 2.0 μg/m3 (8) | 8.0 | |
| March 16, 2019, 11 p.m. | 5.1 ppb (5) | 0.5 ppb (0) | N/A | 5.0 ppb (5) | N/A | N/A | N/A | 0.23 ppb (3) | N/A | 2.0 μg/m3 (8) | 8.0 | |
| March 16, 2019, 10 p.m. | 5.0 ppb (5) | 0.6 ppb (1) | N/A | 4.0 ppb (4) | N/A | N/A | N/A | 0.24 ppb (3) | N/A | 2.0 μg/m3 (8) | 8.0 | |
| March 16, 2019, 9 p.m. | 4.8 ppb (4) | 0.7 ppb (1) | N/A | 4.0 ppb (4) | N/A | N/A | N/A | 0.23 ppb (3) | N/A | 3.0 μg/m3 (12) | 12.0 | |
| March 16, 2019, 8 p.m. | 4.5 ppb (4) | 0.6 ppb (1) | N/A | 4.0 ppb (4) | N/A | N/A | N/A | 0.22 ppb (2) | N/A | 3.0 μg/m3 (12) | 12.0 | |
| March 16, 2019, 7 p.m. | 4.7 ppb (4) | 0.7 ppb (1) | N/A | 4.0 ppb (4) | N/A | N/A | N/A | 0.21 ppb (2) | N/A | 2.0 μg/m3 (8) | 8.0 | |
| March 16, 2019, 6 p.m. | 4.7 ppb (4) | 0.8 ppb (1) | N/A | 4.0 ppb (4) | N/A | N/A | N/A | 0.21 ppb (2) | N/A | 1.0 μg/m3 (4) | 4.0 | |
| March 16, 2019, 5 p.m. | 5.2 ppb (5) | 1.1 ppb (1) | N/A | 4.0 ppb (4) | N/A | N/A | N/A | 0.22 ppb (2) | N/A | -1.0 μg/m3 (0) | 5.0 | |
| March 16, 2019, 4 p.m. | 4.8 ppb (4) | 0.9 ppb (1) | N/A | 4.0 ppb (4) | N/A | N/A | N/A | 0.2 ppb (2) | N/A | 0.0 μg/m3 (0) | 4.0 | |
| March 16, 2019, 3 p.m. | 5.2 ppb (5) | 0.9 ppb (1) | N/A | 4.0 ppb (4) | N/A | N/A | N/A | 0.19 ppb (2) | N/A | 1.0 μg/m3 (4) | 5.0 | |
| March 16, 2019, 2 p.m. | 6.9 ppb (6) | 1.4 ppb (1) | N/A | 5.0 ppb (5) | N/A | N/A | N/A | 0.19 ppb (2) | N/A | -2.0 μg/m3 (0) | 6.0 | |
| March 16, 2019, 1 p.m. | 8.1 ppb (8) | 2.1 ppb (2) | N/A | 6.0 ppb (6) | N/A | N/A | N/A | 0.19 ppb (2) | N/A | -2.0 μg/m3 (0) | 8.0 | |
| March 16, 2019, noon | 7.7 ppb (7) | 1.8 ppb (2) | N/A | 6.0 ppb (6) | N/A | N/A | N/A | 0.17 ppb (2) | N/A | 0.0 μg/m3 (0) | 7.0 | |
| March 16, 2019, 11 a.m. | 6.7 ppb (6) | 1.3 ppb (1) | N/A | 5.0 ppb (5) | N/A | N/A | N/A | 0.17 ppb (2) | N/A | 1.0 μg/m3 (4) | 6.0 | |
| March 16, 2019, 10 a.m. | 6.4 ppb (6) | 1.1 ppb (1) | N/A | 5.0 ppb (5) | N/A | N/A | N/A | 0.16 ppb (2) | N/A | 2.0 μg/m3 (8) | 8.0 | |
| March 16, 2019, 9 a.m. | 6.9 ppb (6) | 1.3 ppb (1) | N/A | 6.0 ppb (6) | N/A | N/A | N/A | 0.17 ppb (2) | N/A | 2.0 μg/m3 (8) | 8.0 | |
| March 16, 2019, 8 a.m. | 6.0 ppb (6) | 0.7 ppb (1) | N/A | 5.0 ppb (5) | N/A | N/A | N/A | 0.15 ppb (2) | N/A | 0.0 μg/m3 (0) | 6.0 | |
| March 16, 2019, 7 a.m. | 8.2 ppb (8) | 1.2 ppb (1) | N/A | 7.0 ppb (6) | N/A | N/A | N/A | 0.16 ppb (2) | N/A | 0.0 μg/m3 (0) | 8.0 | |
| March 16, 2019, 6 a.m. | 9.6 ppb (9) | 1.5 ppb (1) | N/A | 8.0 ppb (7) | N/A | N/A | N/A | 0.17 ppb (2) | N/A | 0.0 μg/m3 (0) | 9.0 | |
| March 16, 2019, 5 a.m. | 11.0 ppb (10) | 1.8 ppb (2) | N/A | 9.0 ppb (8) | N/A | N/A | N/A | 0.18 ppb (2) | N/A | 2.0 μg/m3 (8) | 10.0 | |
| March 16, 2019, 4 a.m. | 10.8 ppb (10) | 1.5 ppb (1) | N/A | 9.0 ppb (8) | N/A | N/A | N/A | N/A | N/A | 2.0 μg/m3 (8) | 10.0 | |
| March 16, 2019, 3 a.m. | 11.6 ppb (11) | 1.4 ppb (1) | N/A | 10.0 ppb (9) | N/A | N/A | N/A | 0.16 ppb (2) | N/A | 2.0 μg/m3 (8) | 11.0 | |
| March 16, 2019, 2 a.m. | 13.9 ppb (13) | 1.9 ppb (2) | N/A | 12.0 ppb (11) | N/A | N/A | N/A | 0.18 ppb (2) | N/A | 4.0 μg/m3 (17) | 17.0 | |
| March 16, 2019, 1 a.m. | 17.2 ppb (16) | 3.0 ppb (3) | N/A | 14.0 ppb (13) | N/A | N/A | N/A | 0.21 ppb (2) | N/A | 6.0 μg/m3 (25) | 25.0 | |
| March 16, 2019, midnight | 31.3 ppb (29) | 10.7 ppb (10) | N/A | 21.0 ppb (19) | N/A | N/A | N/A | 0.32 ppb (4) | N/A | 9.0 μg/m3 (38) | 38.0 | |
| March 15, 2019, 11 p.m. | 33.6 ppb (31) | 11.7 ppb (11) | N/A | 22.0 ppb (20) | N/A | N/A | N/A | 0.34 ppb (4) | N/A | 8.0 μg/m3 (33) | 33.0 | |
| March 15, 2019, 10 p.m. | 31.3 ppb (29) | 11.2 ppb (10) | N/A | 20.0 ppb (19) | N/A | N/A | N/A | 0.32 ppb (4) | N/A | 8.0 μg/m3 (33) | 33.0 | |
| March 15, 2019, 9 p.m. | 25.0 ppb (23) | 7.9 ppb (7) | N/A | 17.0 ppb (16) | N/A | N/A | N/A | 0.29 ppb (3) | N/A | 10.0 μg/m3 (42) | 42.0 | |
| March 15, 2019, 8 p.m. | 24.9 ppb (23) | 7.8 ppb (7) | N/A | 17.0 ppb (16) | N/A | N/A | N/A | 0.3 ppb (3) | N/A | 8.0 μg/m3 (33) | 33.0 | |
| March 15, 2019, 7 p.m. | 25.0 ppb (23) | 7.5 ppb (7) | N/A | 18.0 ppb (17) | N/A | N/A | N/A | 0.3 ppb (3) | N/A | 5.0 μg/m3 (21) | 23.0 | |
| March 15, 2019, 6 p.m. | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 0.29 ppb (3) | N/A | 9.0 μg/m3 (38) | 38.0 | |
| March 15, 2019, 5 p.m. | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 0.28 ppb (3) | N/A | 10.0 μg/m3 (42) | 42.0 | |
| March 15, 2019, 4 p.m. | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 0.27 ppb (3) | N/A | 7.0 μg/m3 (29) | 29.0 | |
| March 15, 2019, 3 p.m. | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 0.33 ppb (4) | N/A | 7.0 μg/m3 (29) | 29.0 | |
| March 15, 2019, 2 p.m. | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 0.33 ppb (4) | N/A | 7.0 μg/m3 (29) | 29.0 | |
| March 15, 2019, 1 p.m. | 39.4 ppb (36) | 14.4 ppb (13) | N/A | 25.0 ppb (23) | N/A | N/A | N/A | 0.32 ppb (4) | N/A | 6.0 μg/m3 (25) | 36.0 | |
| March 15, 2019, noon | 39.0 ppb (36) | 13.7 ppb (13) | N/A | 25.0 ppb (23) | N/A | N/A | N/A | 0.34 ppb (4) | N/A | 9.0 μg/m3 (38) | 38.0 | |
| March 15, 2019, 11 a.m. | 40.7 ppb (38) | 13.7 ppb (13) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.33 ppb (4) | N/A | 10.0 μg/m3 (42) | 42.0 | |
| March 15, 2019, 10 a.m. | 40.7 ppb (38) | 13.7 ppb (13) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.32 ppb (4) | N/A | 10.0 μg/m3 (42) | 42.0 | |
| March 15, 2019, 9 a.m. | 35.9 ppb (33) | 11.9 ppb (11) | N/A | 24.0 ppb (22) | N/A | N/A | N/A | 0.31 ppb (3) | N/A | 9.0 μg/m3 (38) | 38.0 | |
| March 15, 2019, 8 a.m. | N/A | N/A | N/A | N/A | N/A | N/A | N/A | 0.25 ppb (3) | N/A | 6.0 μg/m3 (25) | 25.0 | |
| March 15, 2019, 7 a.m. | 29.7 ppb (28) | 8.0 ppb (7) | N/A | 22.0 ppb (20) | N/A | N/A | N/A | 0.22 ppb (2) | N/A | 6.0 μg/m3 (25) | 28.0 | |
| March 15, 2019, 6 a.m. | 36.2 ppb (34) | 12.3 ppb (11) | N/A | 24.0 ppb (22) | N/A | N/A | N/A | 0.25 ppb (3) | N/A | 4.0 μg/m3 (17) | 34.0 | |
| March 15, 2019, 5 a.m. | 40.9 ppb (38) | 13.7 ppb (13) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.26 ppb (3) | N/A | 6.0 μg/m3 (25) | 38.0 | |
| March 15, 2019, 4 a.m. | 39.6 ppb (37) | 11.8 ppb (11) | N/A | 28.0 ppb (26) | N/A | N/A | N/A | N/A | N/A | 9.0 μg/m3 (38) | 38.0 | |
| March 15, 2019, 3 a.m. | 36.2 ppb (34) | 10.8 ppb (10) | N/A | 25.0 ppb (23) | N/A | N/A | N/A | 0.29 ppb (3) | N/A | 7.0 μg/m3 (29) | 34.0 | |
| March 15, 2019, 2 a.m. | 38.5 ppb (36) | 12.8 ppb (12) | N/A | 26.0 ppb (24) | N/A | N/A | N/A | 0.32 ppb (4) | N/A | 9.0 μg/m3 (38) | 38.0 | |
| March 15, 2019, 1 a.m. | 38.7 ppb (36) | 11.6 ppb (11) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.33 ppb (4) | N/A | 7.0 μg/m3 (29) | 36.0 | |
| March 15, 2019, midnight | 37.0 ppb (34) | 10.9 ppb (10) | N/A | 26.0 ppb (24) | N/A | N/A | N/A | 0.33 ppb (4) | N/A | 6.0 μg/m3 (25) | 34.0 | |
| March 14, 2019, 11 p.m. | 35.0 ppb (32) | 9.4 ppb (9) | N/A | 26.0 ppb (24) | N/A | N/A | N/A | 0.34 ppb (4) | N/A | 4.0 μg/m3 (17) | 32.0 | |
| March 14, 2019, 10 p.m. | 33.6 ppb (31) | 9.3 ppb (9) | N/A | 24.0 ppb (22) | N/A | N/A | N/A | 0.34 ppb (4) | N/A | 5.0 μg/m3 (21) | 31.0 | |
| March 14, 2019, 9 p.m. | 30.8 ppb (29) | 7.9 ppb (7) | N/A | 23.0 ppb (21) | N/A | N/A | N/A | 0.33 ppb (4) | N/A | 5.0 μg/m3 (21) | 29.0 | |
| March 14, 2019, 8 p.m. | 31.4 ppb (29) | 8.2 ppb (8) | N/A | 23.0 ppb (21) | N/A | N/A | N/A | 0.34 ppb (4) | N/A | 5.0 μg/m3 (21) | 29.0 | |
| March 14, 2019, 7 p.m. | 33.2 ppb (31) | 8.3 ppb (8) | N/A | 25.0 ppb (23) | N/A | N/A | N/A | 0.35 ppb (4) | N/A | 5.0 μg/m3 (21) | 31.0 | |
| March 14, 2019, 6 p.m. | 34.4 ppb (32) | 10.9 ppb (10) | N/A | 23.0 ppb (21) | N/A | N/A | N/A | N/A | N/A | 7.0 μg/m3 (29) | 32.0 | |
| March 14, 2019, 5 p.m. | 37.0 ppb (34) | 11.4 ppb (11) | N/A | 26.0 ppb (24) | N/A | N/A | N/A | N/A | N/A | 7.0 μg/m3 (29) | 34.0 | |
| March 14, 2019, 4 p.m. | 45.3 ppb (42) | 17.0 ppb (16) | N/A | 28.0 ppb (26) | N/A | N/A | N/A | N/A | N/A | 5.0 μg/m3 (21) | 42.0 | |
| March 14, 2019, 3 p.m. | 64.4 ppb (61) | 36.0 ppb (33) | N/A | 28.0 ppb (26) | N/A | N/A | N/A | 0.43 ppb (5) | N/A | 7.0 μg/m3 (29) | 61.0 | |
| March 14, 2019, 2 p.m. | 81.1 ppb (79) | 48.9 ppb (45) | N/A | 32.0 ppb (30) | N/A | N/A | N/A | 0.48 ppb (5) | N/A | 10.0 μg/m3 (42) | 79.0 | |
| March 14, 2019, 1 p.m. | 93.8 ppb (92) | 58.4 ppb (55) | N/A | 35.0 ppb (32) | N/A | N/A | N/A | 0.51 ppb (6) | N/A | 12.0 μg/m3 (50) | 92.0 | |
| March 14, 2019, noon | 104.1 ppb (101) | 65.0 ppb (62) | N/A | 39.0 ppb (36) | N/A | N/A | N/A | 0.54 ppb (6) | N/A | 15.0 μg/m3 (56) | 101.0 | |
| March 14, 2019, 11 a.m. | 101.0 ppb (100) | 59.8 ppb (56) | N/A | 41.0 ppb (38) | N/A | N/A | N/A | 0.52 ppb (6) | N/A | 11.0 μg/m3 (46) | 100.0 | |
| March 14, 2019, 10 a.m. | 83.6 ppb (81) | 44.4 ppb (41) | N/A | 39.0 ppb (36) | N/A | N/A | N/A | 0.44 ppb (5) | N/A | 7.0 μg/m3 (29) | 81.0 | |
| March 14, 2019, 9 a.m. | 70.7 ppb (68) | 32.3 ppb (30) | N/A | 38.0 ppb (35) | N/A | N/A | N/A | 0.37 ppb (4) | N/A | 6.0 μg/m3 (25) | 68.0 | |
| March 14, 2019, 8 a.m. | 65.7 ppb (62) | 26.6 ppb (25) | N/A | 39.0 ppb (36) | N/A | N/A | N/A | 0.26 ppb (3) | N/A | 7.0 μg/m3 (29) | 62.0 | |
| March 14, 2019, 7 a.m. | 53.3 ppb (49) | 17.0 ppb (16) | N/A | 36.0 ppb (33) | N/A | N/A | N/A | 0.22 ppb (2) | N/A | 8.0 μg/m3 (33) | 49.0 | |
| March 14, 2019, 6 a.m. | 47.3 ppb (44) | 13.6 ppb (13) | N/A | 34.0 ppb (31) | N/A | N/A | N/A | 0.23 ppb (3) | N/A | 5.0 μg/m3 (21) | 44.0 | |
| March 14, 2019, 5 a.m. | 42.3 ppb (39) | 12.0 ppb (11) | N/A | 30.0 ppb (28) | N/A | N/A | N/A | 0.22 ppb (2) | N/A | 4.0 μg/m3 (17) | 39.0 | |
| March 14, 2019, 4 a.m. | 38.4 ppb (36) | 10.8 ppb (10) | N/A | 28.0 ppb (26) | N/A | N/A | N/A | 0.23 ppb (3) | N/A | 5.0 μg/m3 (21) | 36.0 | |
| March 14, 2019, 3 a.m. | 39.1 ppb (36) | 10.5 ppb (10) | N/A | 29.0 ppb (27) | N/A | N/A | N/A | 0.27 ppb (3) | N/A | 7.0 μg/m3 (29) | 36.0 | |
| March 14, 2019, 2 a.m. | 36.2 ppb (34) | 9.4 ppb (9) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.29 ppb (3) | N/A | 6.0 μg/m3 (25) | 34.0 | |
| March 14, 2019, 1 a.m. | 39.2 ppb (36) | 11.3 ppb (10) | N/A | 28.0 ppb (26) | N/A | N/A | N/A | 0.3 ppb (3) | N/A | 6.0 μg/m3 (25) | 36.0 | |
| March 14, 2019, midnight | 36.2 ppb (34) | 9.3 ppb (9) | N/A | 27.0 ppb (25) | N/A | N/A | N/A | 0.3 ppb (3) | N/A | 8.0 μg/m3 (33) | 34.0 |