AQSQID: 250250042

Site Name: Boston - Roxbury

Location: Boston (Harrison Ave), MA

Reporting: True, Located: True

Current AQI: 25.0

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
March 23, 2019, 4 a.m. 6.0 ppb (6) 1.0 ppb (1) 5.4 ppb (5) 5.0 ppb (5) N/A 0.0 ppb (0) 33.0 ppb (25) 0.22 ppb (2) N/A 4.0 μg/m3 (17) 25.0
 
March 23, 2019, 3 a.m. 6.0 ppb (6) 0.0 ppb (0) 5.6 ppb (5) 5.0 ppb (5) N/A 0.0 ppb (0) 40.0 ppb (31) 0.21 ppb (2) N/A 2.0 μg/m3 (8) 31.0
 
March 23, 2019, 2 a.m. 7.0 ppb (6) 1.0 ppb (1) 6.8 ppb (6) 6.0 ppb (6) N/A 0.0 ppb (0) 42.0 ppb (32) 0.24 ppb (3) N/A 4.0 μg/m3 (17) 32.0
 
March 23, 2019, 1 a.m. 7.0 ppb (6) 1.0 ppb (1) 6.8 ppb (6) 6.0 ppb (6) N/A 0.0 ppb (0) 43.0 ppb (33) 0.23 ppb (3) N/A 5.0 μg/m3 (21) 33.0
 
March 23, 2019, midnight 7.0 ppb (6) 1.0 ppb (1) 7.0 ppb (6) 6.0 ppb (6) N/A 0.0 ppb (0) 44.0 ppb (34) 0.22 ppb (2) N/A 6.0 μg/m3 (25) 34.0
 
March 22, 2019, 11 p.m. 8.0 ppb (7) 1.0 ppb (1) 7.5 ppb (7) 7.0 ppb (6) N/A 0.0 ppb (0) 43.0 ppb (33) 0.23 ppb (3) N/A 9.0 μg/m3 (38) 38.0
 
March 22, 2019, 10 p.m. 8.0 ppb (7) 1.0 ppb (1) 7.7 ppb (7) 7.0 ppb (6) N/A 0.0 ppb (0) 42.0 ppb (32) 0.23 ppb (3) N/A 5.0 μg/m3 (21) 32.0
 
March 22, 2019, 9 p.m. 9.0 ppb (8) 2.0 ppb (2) 9.0 ppb (8) 7.0 ppb (6) N/A 0.0 ppb (0) 40.0 ppb (31) 0.25 ppb (3) N/A 4.0 μg/m3 (17) 31.0
 
March 22, 2019, 8 p.m. 9.0 ppb (8) 2.0 ppb (2) 9.1 ppb (8) 7.0 ppb (6) N/A 0.0 ppb (0) 40.0 ppb (31) 0.26 ppb (3) N/A 5.0 μg/m3 (21) 31.0
 
March 22, 2019, 7 p.m. 13.0 ppb (12) 3.0 ppb (3) 12.3 ppb (11) 10.0 ppb (9) N/A 0.0 ppb (0) 37.0 ppb (28) 0.27 ppb (3) N/A 6.0 μg/m3 (25) 28.0
 
March 22, 2019, 6 p.m. 23.0 ppb (21) 5.0 ppb (5) 21.6 ppb (20) 17.0 ppb (16) N/A 0.0 ppb (0) 32.0 ppb (25) 0.26 ppb (3) N/A 3.0 μg/m3 (12) 25.0
 
March 22, 2019, 5 p.m. 19.0 ppb (18) 4.0 ppb (4) 18.8 ppb (17) 15.0 ppb (14) N/A 0.0 ppb (0) 32.0 ppb (25) 0.31 ppb (3) N/A 4.0 μg/m3 (17) 25.0
 
March 22, 2019, 4 p.m. 24.0 ppb (22) 4.0 ppb (4) 24.1 ppb (22) 20.0 ppb (19) N/A 0.0 ppb (0) 29.0 ppb (22) 0.31 ppb (3) N/A 6.0 μg/m3 (25) 25.0
 
March 22, 2019, 3 p.m. 15.0 ppb (14) 2.0 ppb (2) 14.6 ppb (14) 13.0 ppb (12) N/A 0.0 ppb (0) 35.0 ppb (27) 0.22 ppb (2) N/A 5.0 μg/m3 (21) 27.0
 
March 22, 2019, 2 p.m. 14.0 ppb (13) 2.0 ppb (2) 13.3 ppb (12) 12.0 ppb (11) N/A 0.0 ppb (0) 37.0 ppb (28) 0.2 ppb (2) N/A 7.0 μg/m3 (29) 29.0
 
March 22, 2019, 1 p.m. 10.0 ppb (9) 1.0 ppb (1) 9.5 ppb (9) 9.0 ppb (8) N/A 0.0 ppb (0) 41.0 ppb (32) 0.19 ppb (2) N/A 7.0 μg/m3 (29) 32.0
 
March 22, 2019, noon 11.0 ppb (10) 1.0 ppb (1) 10.3 ppb (10) 9.0 ppb (8) N/A 0.0 ppb (0) 41.0 ppb (32) 0.19 ppb (2) N/A 5.0 μg/m3 (21) 32.0
 
March 22, 2019, 11 a.m. 13.0 ppb (12) 1.0 ppb (1) 12.5 ppb (12) 12.0 ppb (11) N/A 0.0 ppb (0) 39.0 ppb (30) 0.19 ppb (2) N/A 2.0 μg/m3 (8) 30.0
 
March 22, 2019, 10 a.m. 11.0 ppb (10) 1.0 ppb (1) 10.3 ppb (10) 10.0 ppb (9) N/A N/A 41.0 ppb (32) 0.17 ppb (2) N/A 5.0 μg/m3 (21) 32.0
 
March 22, 2019, 9 a.m. 8.0 ppb (7) 1.0 ppb (1) 7.3 ppb (7) 7.0 ppb (6) N/A N/A 42.0 ppb (32) 0.15 ppb (2) N/A 7.0 μg/m3 (29) 32.0
 
March 22, 2019, 8 a.m. 7.0 ppb (6) 0.0 ppb (0) N/A 6.0 ppb (6) N/A N/A 43.0 ppb (33) 0.15 ppb (2) N/A 9.0 μg/m3 (38) 38.0
 
March 22, 2019, 7 a.m. 5.0 ppb (5) 0.0 ppb (0) N/A 5.0 ppb (5) N/A 0.0 ppb (0) 44.0 ppb (34) 0.15 ppb (2) N/A 7.0 μg/m3 (29) 34.0
 
March 22, 2019, 6 a.m. 6.0 ppb (6) 0.0 ppb (0) N/A 6.0 ppb (6) N/A 0.0 ppb (0) 43.0 ppb (33) 0.15 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 22, 2019, 5 a.m. 7.0 ppb (6) 0.0 ppb (0) N/A 6.0 ppb (6) N/A 0.0 ppb (0) 42.0 ppb (32) 0.16 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 22, 2019, 4 a.m. 9.0 ppb (8) 0.0 ppb (0) 9.5 ppb (9) 9.0 ppb (8) N/A 0.0 ppb (0) 39.0 ppb (30) 0.15 ppb (2) N/A 7.0 μg/m3 (29) 30.0
 
March 22, 2019, 3 a.m. 10.0 ppb (9) 1.0 ppb (1) 10.0 ppb (9) 10.0 ppb (9) N/A 0.0 ppb (0) 39.0 ppb (30) 0.16 ppb (2) N/A 7.0 μg/m3 (29) 30.0
 
March 22, 2019, 2 a.m. 10.0 ppb (9) 0.0 ppb (0) 10.0 ppb (9) 10.0 ppb (9) N/A 0.0 ppb (0) 39.0 ppb (30) 0.15 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 22, 2019, 1 a.m. 14.0 ppb (13) 1.0 ppb (1) 13.9 ppb (13) 13.0 ppb (12) N/A 0.0 ppb (0) 36.0 ppb (28) 0.17 ppb (2) N/A 9.0 μg/m3 (38) 38.0
 
March 22, 2019, midnight 10.0 ppb (9) 1.0 ppb (1) 10.7 ppb (10) 10.0 ppb (9) N/A 0.0 ppb (0) 38.0 ppb (29) 0.18 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 21, 2019, 11 p.m. 9.0 ppb (8) 1.0 ppb (1) 8.7 ppb (8) 8.0 ppb (7) N/A 0.0 ppb (0) 41.0 ppb (32) 0.19 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 21, 2019, 10 p.m. 13.0 ppb (12) 1.0 ppb (1) 13.0 ppb (12) 12.0 ppb (11) N/A 0.0 ppb (0) 40.0 ppb (31) 0.23 ppb (3) N/A 8.0 μg/m3 (33) 33.0
 
March 21, 2019, 9 p.m. 13.0 ppb (12) 2.0 ppb (2) 13.3 ppb (12) 12.0 ppb (11) N/A 0.0 ppb (0) 43.0 ppb (33) 0.25 ppb (3) N/A 8.0 μg/m3 (33) 33.0
 
March 21, 2019, 8 p.m. 13.0 ppb (12) 2.0 ppb (2) 11.6 ppb (11) 10.0 ppb (9) N/A 0.0 ppb (0) 49.0 ppb (38) 0.3 ppb (3) N/A 10.0 μg/m3 (42) 42.0
 
March 21, 2019, 7 p.m. 12.0 ppb (11) 3.0 ppb (3) 10.9 ppb (10) 9.0 ppb (8) N/A 0.0 ppb (0) 50.0 ppb (38) 0.24 ppb (3) N/A 7.0 μg/m3 (29) 38.0
 
March 21, 2019, 6 p.m. 9.0 ppb (8) 2.0 ppb (2) 8.8 ppb (8) 7.0 ppb (6) N/A 0.0 ppb (0) 50.0 ppb (38) 0.21 ppb (2) N/A 6.0 μg/m3 (25) 38.0
 
March 21, 2019, 5 p.m. 8.0 ppb (7) 2.0 ppb (2) 7.8 ppb (7) 6.0 ppb (6) N/A 0.0 ppb (0) 50.0 ppb (38) 0.2 ppb (2) N/A 6.0 μg/m3 (25) 38.0
 
March 21, 2019, 4 p.m. 10.0 ppb (9) 2.0 ppb (2) 9.9 ppb (9) 8.0 ppb (7) N/A 0.0 ppb (0) 47.0 ppb (36) 0.22 ppb (2) N/A 6.0 μg/m3 (25) 36.0
 
March 21, 2019, 3 p.m. 11.0 ppb (10) 3.0 ppb (3) 10.2 ppb (9) 8.0 ppb (7) N/A 0.0 ppb (0) 46.0 ppb (35) 0.23 ppb (3) N/A 8.0 μg/m3 (33) 35.0
 
March 21, 2019, 2 p.m. 11.0 ppb (10) 2.0 ppb (2) 11.4 ppb (11) 9.0 ppb (8) N/A 0.0 ppb (0) 44.0 ppb (34) 0.22 ppb (2) N/A 10.0 μg/m3 (42) 42.0
 
March 21, 2019, 1 p.m. 21.0 ppb (19) 6.0 ppb (6) 19.0 ppb (18) 15.0 ppb (14) N/A 0.0 ppb (0) 39.0 ppb (30) 0.24 ppb (3) N/A 10.0 μg/m3 (42) 42.0
 
March 21, 2019, noon 24.0 ppb (22) 5.0 ppb (5) 24.3 ppb (23) 19.0 ppb (18) N/A 0.0 ppb (0) 34.0 ppb (26) 0.29 ppb (3) N/A 12.0 μg/m3 (50) 50.0
 
March 21, 2019, 11 a.m. 42.0 ppb (39) 7.0 ppb (6) 39.7 ppb (37) 35.0 ppb (32) N/A 0.0 ppb (0) 19.0 ppb (15) 0.39 ppb (4) N/A 9.0 μg/m3 (38) 39.0
 
March 21, 2019, 10 a.m. 40.0 ppb (37) 5.0 ppb (5) 40.0 ppb (37) 35.0 ppb (32) N/A 0.0 ppb (0) 16.0 ppb (12) 0.36 ppb (4) N/A 9.0 μg/m3 (38) 38.0
 
March 21, 2019, 9 a.m. 28.0 ppb (26) 3.0 ppb (3) 27.5 ppb (25) 25.0 ppb (23) N/A 0.0 ppb (0) 24.0 ppb (18) 0.27 ppb (3) N/A 8.0 μg/m3 (33) 33.0
 
March 21, 2019, 8 a.m. 16.0 ppb (15) 0.0 ppb (0) 16.4 ppb (15) 16.0 ppb (15) N/A 0.0 ppb (0) 33.0 ppb (25) 0.21 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 21, 2019, 7 a.m. 13.0 ppb (12) 1.0 ppb (1) 13.4 ppb (12) 12.0 ppb (11) N/A 0.0 ppb (0) 36.0 ppb (28) 0.17 ppb (2) N/A 10.0 μg/m3 (42) 42.0
 
March 21, 2019, 6 a.m. 11.0 ppb (10) 0.0 ppb (0) 11.3 ppb (10) 11.0 ppb (10) N/A 0.0 ppb (0) 38.0 ppb (29) 0.19 ppb (2) N/A 9.0 μg/m3 (38) 38.0
 
March 21, 2019, 5 a.m. 12.0 ppb (11) 0.0 ppb (0) 12.3 ppb (11) 12.0 ppb (11) N/A 0.0 ppb (0) 37.0 ppb (28) 0.19 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 21, 2019, 4 a.m. 11.0 ppb (10) 1.0 ppb (1) 11.2 ppb (10) 11.0 ppb (10) N/A 0.0 ppb (0) 41.0 ppb (32) 0.2 ppb (2) N/A 7.0 μg/m3 (29) 32.0
 
March 21, 2019, 3 a.m. 12.0 ppb (11) 1.0 ppb (1) 11.8 ppb (11) 11.0 ppb (10) N/A 0.0 ppb (0) 41.0 ppb (32) 0.21 ppb (2) N/A 11.0 μg/m3 (46) 46.0
 
March 21, 2019, 2 a.m. 9.0 ppb (8) 1.0 ppb (1) 9.6 ppb (9) 9.0 ppb (8) N/A 0.0 ppb (0) 44.0 ppb (34) 0.2 ppb (2) N/A 10.0 μg/m3 (42) 42.0
 
March 21, 2019, 1 a.m. 9.0 ppb (8) 0.0 ppb (0) 9.6 ppb (9) 9.0 ppb (8) N/A 0.0 ppb (0) 44.0 ppb (34) 0.25 ppb (3) N/A 9.0 μg/m3 (38) 38.0
 
March 21, 2019, midnight 10.0 ppb (9) 1.0 ppb (1) 10.9 ppb (10) 9.0 ppb (8) N/A 0.0 ppb (0) 44.0 ppb (34) 0.24 ppb (3) N/A 13.0 μg/m3 (52) 52.0
 
March 20, 2019, 11 p.m. 11.0 ppb (10) 1.0 ppb (1) 11.0 ppb (10) 10.0 ppb (9) N/A 0.0 ppb (0) 45.0 ppb (35) 0.29 ppb (3) N/A 12.0 μg/m3 (50) 50.0
 
March 20, 2019, 10 p.m. 10.0 ppb (9) 1.0 ppb (1) 10.0 ppb (9) 8.0 ppb (7) N/A 0.0 ppb (0) 48.0 ppb (37) 0.25 ppb (3) N/A 11.0 μg/m3 (46) 46.0
 
March 20, 2019, 9 p.m. 9.0 ppb (8) 2.0 ppb (2) 9.8 ppb (9) 7.0 ppb (6) N/A 0.0 ppb (0) 49.0 ppb (38) 0.23 ppb (3) N/A 10.0 μg/m3 (42) 42.0
 
March 20, 2019, 8 p.m. 12.0 ppb (11) 3.0 ppb (3) 12.7 ppb (12) 9.0 ppb (8) N/A 0.0 ppb (0) 46.0 ppb (35) 0.26 ppb (3) N/A 15.0 μg/m3 (56) 56.0
 
March 20, 2019, 7 p.m. 18.0 ppb (17) 4.0 ppb (4) 19.5 ppb (18) 14.0 ppb (13) N/A 0.0 ppb (0) 40.0 ppb (31) 0.24 ppb (3) N/A 12.0 μg/m3 (50) 50.0
 
March 20, 2019, 6 p.m. 13.0 ppb (12) 3.0 ppb (3) 14.2 ppb (13) 10.0 ppb (9) N/A 0.0 ppb (0) 42.0 ppb (32) 0.22 ppb (2) N/A 7.0 μg/m3 (29) 32.0
 
March 20, 2019, 5 p.m. 16.0 ppb (15) 5.0 ppb (5) 17.1 ppb (16) 11.0 ppb (10) N/A 0.0 ppb (0) 38.0 ppb (29) 0.23 ppb (3) N/A 8.0 μg/m3 (33) 33.0
 
March 20, 2019, 4 p.m. 12.0 ppb (11) 3.0 ppb (3) 12.9 ppb (12) 9.0 ppb (8) N/A 0.0 ppb (0) 41.0 ppb (32) 0.21 ppb (2) N/A N/A 32.0
 
March 20, 2019, 3 p.m. 14.0 ppb (13) 4.0 ppb (4) 14.2 ppb (13) 10.0 ppb (9) N/A 0.0 ppb (0) 41.0 ppb (32) 0.24 ppb (3) N/A 8.0 μg/m3 (33) 33.0
 
March 20, 2019, 2 p.m. 21.0 ppb (19) 6.0 ppb (6) 21.0 ppb (19) 15.0 ppb (14) N/A 0.0 ppb (0) 36.0 ppb (28) 0.25 ppb (3) N/A 10.0 μg/m3 (42) 42.0
 
March 20, 2019, 1 p.m. 31.0 ppb (29) 11.0 ppb (10) 31.6 ppb (29) 21.0 ppb (19) N/A 0.0 ppb (0) 29.0 ppb (22) 0.31 ppb (3) N/A 11.0 μg/m3 (46) 46.0
 
March 20, 2019, noon 68.0 ppb (65) 31.0 ppb (29) 66.1 ppb (63) 37.0 ppb (34) N/A 1.0 ppb (1) 13.0 ppb (10) 0.49 ppb (5) N/A 13.0 μg/m3 (52) 65.0
 
March 20, 2019, 11 a.m. 110.0 ppb (102) 63.0 ppb (60) 111.5 ppb (102) 46.0 ppb (43) N/A 1.0 ppb (1) 2.0 ppb (2) 0.68 ppb (8) N/A 9.0 μg/m3 (38) 102.0
 
March 20, 2019, 10 a.m. 115.0 ppb (103) 66.0 ppb (63) 116.9 ppb (103) 49.0 ppb (45) N/A 1.0 ppb (1) 0.0 ppb (0) N/A N/A 12.0 μg/m3 (50) 103.0
 
March 20, 2019, 9 a.m. 88.0 ppb (86) 41.0 ppb (38) 89.8 ppb (88) 47.0 ppb (44) N/A 1.0 ppb (1) 0.0 ppb (0) 0.55 ppb (6) N/A 10.0 μg/m3 (42) 88.0
 
March 20, 2019, 8 a.m. 72.0 ppb (69) 28.0 ppb (26) 74.0 ppb (71) 44.0 ppb (41) N/A 1.0 ppb (1) N/A 0.5 ppb (6) N/A 12.0 μg/m3 (50) 71.0
 
March 20, 2019, 7 a.m. N/A N/A 40.8 ppb (38) N/A N/A 0.0 ppb (0) 8.0 ppb (6) 0.38 ppb (4) N/A 8.0 μg/m3 (33) 38.0
 
March 20, 2019, 6 a.m. N/A N/A 42.8 ppb (40) N/A N/A 0.0 ppb (0) 11.0 ppb (8) 0.37 ppb (4) N/A 8.0 μg/m3 (33) 40.0
 
March 20, 2019, 5 a.m. N/A N/A 72.9 ppb (70) N/A N/A 1.0 ppb (1) 1.0 ppb (1) 0.5 ppb (6) N/A 17.0 μg/m3 (61) 70.0
 
March 20, 2019, 4 a.m. 88.0 ppb (86) 36.0 ppb (33) 87.5 ppb (86) 52.0 ppb (48) N/A 1.0 ppb (1) 0.0 ppb (0) 0.61 ppb (7) N/A 9.0 μg/m3 (38) 86.0
 
March 20, 2019, 3 a.m. 76.0 ppb (73) 27.0 ppb (25) 77.1 ppb (75) 49.0 ppb (45) N/A 1.0 ppb (1) 1.0 ppb (1) 0.63 ppb (7) N/A 14.0 μg/m3 (54) 75.0
 
March 20, 2019, 2 a.m. 54.0 ppb (50) 13.0 ppb (12) 52.3 ppb (48) 41.0 ppb (38) N/A 0.0 ppb (0) 7.0 ppb (5) 0.5 ppb (6) N/A 10.0 μg/m3 (42) 50.0
 
March 20, 2019, 1 a.m. 36.0 ppb (33) 8.0 ppb (7) 33.4 ppb (31) 28.0 ppb (26) N/A 0.0 ppb (0) 22.0 ppb (17) 0.23 ppb (3) N/A 6.0 μg/m3 (25) 33.0
 
March 20, 2019, midnight 21.0 ppb (19) 2.0 ppb (2) 20.7 ppb (19) 18.0 ppb (17) N/A 0.0 ppb (0) 29.0 ppb (22) 0.22 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
March 19, 2019, 11 p.m. 12.0 ppb (11) 1.0 ppb (1) 11.7 ppb (11) 11.0 ppb (10) N/A 0.0 ppb (0) 37.0 ppb (28) 0.21 ppb (2) N/A 6.0 μg/m3 (25) 28.0
 
March 19, 2019, 10 p.m. 11.0 ppb (10) 1.0 ppb (1) 10.5 ppb (10) 10.0 ppb (9) N/A 0.0 ppb (0) 39.0 ppb (30) 0.24 ppb (3) N/A 6.0 μg/m3 (25) 30.0
 
March 19, 2019, 9 p.m. 11.0 ppb (10) 2.0 ppb (2) 10.3 ppb (10) 9.0 ppb (8) N/A 0.0 ppb (0) 40.0 ppb (31) 0.19 ppb (2) N/A 7.0 μg/m3 (29) 31.0
 
March 19, 2019, 8 p.m. 9.0 ppb (8) 2.0 ppb (2) 9.3 ppb (9) 7.0 ppb (6) N/A 0.0 ppb (0) 42.0 ppb (32) 0.19 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 19, 2019, 7 p.m. 9.0 ppb (8) 2.0 ppb (2) 8.9 ppb (8) 7.0 ppb (6) N/A 0.0 ppb (0) 42.0 ppb (32) 0.2 ppb (2) N/A 6.0 μg/m3 (25) 32.0
 
March 19, 2019, 6 p.m. 8.0 ppb (7) 2.0 ppb (2) 8.4 ppb (8) 6.0 ppb (6) N/A 0.0 ppb (0) 43.0 ppb (33) 0.19 ppb (2) N/A 7.0 μg/m3 (29) 33.0
 
March 19, 2019, 5 p.m. 8.0 ppb (7) 2.0 ppb (2) 7.8 ppb (7) 6.0 ppb (6) N/A 0.0 ppb (0) 43.0 ppb (33) 0.18 ppb (2) N/A 6.0 μg/m3 (25) 33.0
 
March 19, 2019, 4 p.m. 8.0 ppb (7) 3.0 ppb (3) 8.8 ppb (8) 6.0 ppb (6) N/A 0.0 ppb (0) 42.0 ppb (32) 0.19 ppb (2) N/A 6.0 μg/m3 (25) 32.0
 
March 19, 2019, 3 p.m. 9.0 ppb (8) 2.0 ppb (2) 8.7 ppb (8) 7.0 ppb (6) N/A 0.0 ppb (0) 40.0 ppb (31) 0.18 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 19, 2019, 2 p.m. 12.0 ppb (11) 3.0 ppb (3) N/A 8.0 ppb (7) N/A 0.0 ppb (0) 37.0 ppb (28) 0.19 ppb (2) N/A 11.0 μg/m3 (46) 46.0
 
March 19, 2019, 1 p.m. 16.0 ppb (15) 5.0 ppb (5) N/A 12.0 ppb (11) N/A 0.0 ppb (0) 34.0 ppb (26) 0.22 ppb (2) N/A 12.0 μg/m3 (50) 50.0
 
March 19, 2019, noon 33.0 ppb (31) 10.0 ppb (9) N/A 23.0 ppb (21) N/A 0.0 ppb (0) 23.0 ppb (18) 0.3 ppb (3) N/A 9.0 μg/m3 (38) 38.0
 
March 19, 2019, 11 a.m. 40.0 ppb (37) 10.0 ppb (9) N/A 30.0 ppb (28) N/A 0.0 ppb (0) 15.0 ppb (12) 0.4 ppb (4) N/A 11.0 μg/m3 (46) 46.0
 
March 19, 2019, 10 a.m. 37.0 ppb (34) 5.0 ppb (5) 32.9 ppb (30) 32.0 ppb (30) N/A N/A 14.0 ppb (11) 0.34 ppb (4) N/A 8.0 μg/m3 (33) 34.0
 
March 19, 2019, 9 a.m. 27.0 ppb (25) 2.0 ppb (2) 24.1 ppb (22) 24.0 ppb (22) N/A N/A 19.0 ppb (15) 0.3 ppb (3) N/A 10.0 μg/m3 (42) 42.0
 
March 19, 2019, 8 a.m. 24.0 ppb (22) 1.0 ppb (1) N/A 23.0 ppb (21) N/A N/A 20.0 ppb (15) 0.31 ppb (3) N/A 9.0 μg/m3 (38) 38.0
 
March 19, 2019, 7 a.m. 32.0 ppb (30) 2.0 ppb (2) N/A 30.0 ppb (28) N/A 0.0 ppb (0) 14.0 ppb (11) 0.32 ppb (4) N/A 6.0 μg/m3 (25) 30.0
 
March 19, 2019, 6 a.m. 46.0 ppb (43) 7.0 ppb (6) N/A 39.0 ppb (36) N/A 0.0 ppb (0) 8.0 ppb (6) 0.34 ppb (4) N/A 7.0 μg/m3 (29) 43.0
 
March 19, 2019, 5 a.m. 45.0 ppb (42) 6.0 ppb (6) N/A 39.0 ppb (36) N/A 0.0 ppb (0) 8.0 ppb (6) 0.35 ppb (4) N/A 9.0 μg/m3 (38) 42.0
 
March 19, 2019, 4 a.m. 68.0 ppb (65) 22.0 ppb (20) 59.9 ppb (56) 46.0 ppb (43) N/A 1.0 ppb (1) 4.0 ppb (3) 0.38 ppb (4) N/A 10.0 μg/m3 (42) 65.0
 
March 19, 2019, 3 a.m. 47.0 ppb (44) 9.0 ppb (8) 43.2 ppb (40) 38.0 ppb (35) N/A 0.0 ppb (0) 10.0 ppb (8) 0.34 ppb (4) N/A 7.0 μg/m3 (29) 44.0
 
March 19, 2019, 2 a.m. 30.0 ppb (28) 3.0 ppb (3) 27.4 ppb (25) 27.0 ppb (25) N/A 0.0 ppb (0) 21.0 ppb (16) 0.33 ppb (4) N/A 7.0 μg/m3 (29) 29.0
 
March 19, 2019, 1 a.m. 29.0 ppb (27) 3.0 ppb (3) 26.9 ppb (25) 26.0 ppb (24) N/A 0.0 ppb (0) 22.0 ppb (17) 0.33 ppb (4) N/A 6.0 μg/m3 (25) 27.0
 
March 19, 2019, midnight 30.0 ppb (28) 5.0 ppb (5) 27.6 ppb (26) 25.0 ppb (23) N/A 0.0 ppb (0) 23.0 ppb (18) 0.25 ppb (3) N/A 7.0 μg/m3 (29) 29.0
 
March 18, 2019, 11 p.m. 14.0 ppb (13) 1.0 ppb (1) 13.9 ppb (13) 12.0 ppb (11) N/A 0.0 ppb (0) 36.0 ppb (28) 0.23 ppb (3) N/A 4.0 μg/m3 (17) 28.0
 
March 18, 2019, 10 p.m. 15.0 ppb (14) 2.0 ppb (2) 14.3 ppb (13) 13.0 ppb (12) N/A 0.0 ppb (0) 36.0 ppb (28) 0.25 ppb (3) N/A 5.0 μg/m3 (21) 28.0
 
March 18, 2019, 9 p.m. 10.0 ppb (9) 2.0 ppb (2) 10.1 ppb (9) 8.0 ppb (7) N/A 0.0 ppb (0) 40.0 ppb (31) 0.22 ppb (2) N/A 5.0 μg/m3 (21) 31.0
 
March 18, 2019, 8 p.m. 7.0 ppb (6) 2.0 ppb (2) 6.4 ppb (6) 5.0 ppb (5) N/A 0.0 ppb (0) 44.0 ppb (34) 0.2 ppb (2) N/A 5.0 μg/m3 (21) 34.0
 
March 18, 2019, 7 p.m. 8.0 ppb (7) 2.0 ppb (2) 8.1 ppb (8) 6.0 ppb (6) N/A 0.0 ppb (0) 44.0 ppb (34) 0.2 ppb (2) N/A 6.0 μg/m3 (25) 34.0
 
March 18, 2019, 6 p.m. 10.0 ppb (9) 3.0 ppb (3) 9.4 ppb (9) 7.0 ppb (6) N/A 0.0 ppb (0) 42.0 ppb (32) 0.2 ppb (2) N/A 4.0 μg/m3 (17) 32.0
 
March 18, 2019, 5 p.m. 9.0 ppb (8) 3.0 ppb (3) 8.5 ppb (8) 6.0 ppb (6) N/A 0.0 ppb (0) 42.0 ppb (32) 0.19 ppb (2) N/A 2.0 μg/m3 (8) 32.0
 
March 18, 2019, 4 p.m. 7.0 ppb (6) 2.0 ppb (2) 6.9 ppb (6) 5.0 ppb (5) N/A 0.0 ppb (0) 43.0 ppb (33) 0.18 ppb (2) N/A 3.0 μg/m3 (12) 33.0
 
March 18, 2019, 3 p.m. 10.0 ppb (9) 3.0 ppb (3) 9.9 ppb (9) 7.0 ppb (6) N/A 0.0 ppb (0) 40.0 ppb (31) 0.19 ppb (2) N/A 5.0 μg/m3 (21) 31.0
 
March 18, 2019, 2 p.m. 11.0 ppb (10) 4.0 ppb (4) 11.1 ppb (10) 8.0 ppb (7) N/A 0.0 ppb (0) 38.0 ppb (29) 0.21 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 18, 2019, 1 p.m. 18.0 ppb (17) 6.0 ppb (6) 17.6 ppb (16) 12.0 ppb (11) N/A 0.0 ppb (0) 33.0 ppb (25) 0.21 ppb (2) N/A 11.0 μg/m3 (46) 46.0
 
March 18, 2019, noon 26.0 ppb (24) 7.0 ppb (6) 24.5 ppb (23) 19.0 ppb (18) N/A 0.0 ppb (0) 26.0 ppb (20) 0.27 ppb (3) N/A 11.0 μg/m3 (46) 46.0
 
March 18, 2019, 11 a.m. 31.0 ppb (29) 6.0 ppb (6) 29.0 ppb (27) 25.0 ppb (23) N/A 0.0 ppb (0) 21.0 ppb (16) 0.29 ppb (3) N/A 9.0 μg/m3 (38) 38.0
 
March 18, 2019, 10 a.m. 31.0 ppb (29) 5.0 ppb (5) 29.0 ppb (27) 26.0 ppb (24) N/A 0.0 ppb (0) 19.0 ppb (15) 0.27 ppb (3) N/A 6.0 μg/m3 (25) 29.0
 
March 18, 2019, 9 a.m. 20.0 ppb (19) 3.0 ppb (3) 19.6 ppb (18) 17.0 ppb (16) N/A 0.0 ppb (0) 26.0 ppb (20) 0.22 ppb (2) N/A 7.0 μg/m3 (29) 29.0
 
March 18, 2019, 8 a.m. 13.0 ppb (12) 1.0 ppb (1) 11.7 ppb (11) 12.0 ppb (11) N/A 0.0 ppb (0) 31.0 ppb (24) 0.18 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
March 18, 2019, 7 a.m. 15.0 ppb (14) 1.0 ppb (1) 13.4 ppb (12) 14.0 ppb (13) N/A 0.0 ppb (0) 29.0 ppb (22) 0.19 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
March 18, 2019, 6 a.m. 17.0 ppb (16) 1.0 ppb (1) 14.2 ppb (13) 15.0 ppb (14) N/A 0.0 ppb (0) 29.0 ppb (22) 0.18 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
March 18, 2019, 5 a.m. 19.0 ppb (18) 3.0 ppb (3) 17.5 ppb (16) 15.0 ppb (14) N/A 0.0 ppb (0) 28.0 ppb (22) 0.15 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
March 18, 2019, 4 a.m. 12.0 ppb (11) 1.0 ppb (1) 11.4 ppb (11) 11.0 ppb (10) N/A 0.0 ppb (0) 32.0 ppb (25) 0.17 ppb (2) N/A 2.0 μg/m3 (8) 25.0
 
March 18, 2019, 3 a.m. 13.0 ppb (12) 1.0 ppb (1) 11.8 ppb (11) 11.0 ppb (10) N/A 0.0 ppb (0) 34.0 ppb (26) 0.16 ppb (2) N/A 3.0 μg/m3 (12) 26.0
 
March 18, 2019, 2 a.m. 12.0 ppb (11) 1.0 ppb (1) 11.3 ppb (10) 11.0 ppb (10) N/A 0.0 ppb (0) 33.0 ppb (25) 0.21 ppb (2) N/A 4.0 μg/m3 (17) 25.0
 
March 18, 2019, 1 a.m. 13.0 ppb (12) 1.0 ppb (1) 11.9 ppb (11) 12.0 ppb (11) N/A 0.0 ppb (0) 33.0 ppb (25) 0.23 ppb (3) N/A 5.0 μg/m3 (21) 25.0
 
March 18, 2019, midnight 15.0 ppb (14) 2.0 ppb (2) 13.5 ppb (12) 13.0 ppb (12) N/A 0.0 ppb (0) 32.0 ppb (25) 0.22 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
March 17, 2019, 11 p.m. 9.0 ppb (8) 1.0 ppb (1) 8.7 ppb (8) 9.0 ppb (8) N/A 0.0 ppb (0) 37.0 ppb (28) 0.22 ppb (2) N/A 6.0 μg/m3 (25) 28.0
 
March 17, 2019, 10 p.m. 8.0 ppb (7) 1.0 ppb (1) 7.5 ppb (7) 7.0 ppb (6) N/A 0.0 ppb (0) 40.0 ppb (31) 0.22 ppb (2) N/A 9.0 μg/m3 (38) 38.0
 
March 17, 2019, 9 p.m. 6.0 ppb (6) 1.0 ppb (1) 5.9 ppb (5) 5.0 ppb (5) N/A 0.0 ppb (0) 41.0 ppb (32) 0.19 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 17, 2019, 8 p.m. 5.0 ppb (5) 1.0 ppb (1) 4.6 ppb (4) 4.0 ppb (4) N/A 0.0 ppb (0) 43.0 ppb (33) 0.18 ppb (2) N/A 4.0 μg/m3 (17) 33.0
 
March 17, 2019, 7 p.m. 8.0 ppb (7) 2.0 ppb (2) 7.9 ppb (7) 6.0 ppb (6) N/A 0.0 ppb (0) 41.0 ppb (32) 0.19 ppb (2) N/A 3.0 μg/m3 (12) 32.0
 
March 17, 2019, 6 p.m. 5.0 ppb (5) 2.0 ppb (2) 5.2 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 42.0 ppb (32) 0.17 ppb (2) N/A 3.0 μg/m3 (12) 32.0
 
March 17, 2019, 5 p.m. 6.0 ppb (6) 2.0 ppb (2) 5.4 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 41.0 ppb (32) 0.18 ppb (2) N/A 6.0 μg/m3 (25) 32.0
 
March 17, 2019, 4 p.m. 6.0 ppb (6) 2.0 ppb (2) 5.4 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 41.0 ppb (32) 0.17 ppb (2) N/A 7.0 μg/m3 (29) 32.0
 
March 17, 2019, 3 p.m. 6.0 ppb (6) 2.0 ppb (2) 5.6 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 41.0 ppb (32) 0.16 ppb (2) N/A 6.0 μg/m3 (25) 32.0
 
March 17, 2019, 2 p.m. 10.0 ppb (9) 3.0 ppb (3) 9.3 ppb (9) 7.0 ppb (6) N/A 0.0 ppb (0) 38.0 ppb (29) 0.17 ppb (2) N/A 10.0 μg/m3 (42) 42.0
 
March 17, 2019, 1 p.m. 9.0 ppb (8) 3.0 ppb (3) 8.3 ppb (8) 6.0 ppb (6) N/A 0.0 ppb (0) 39.0 ppb (30) 0.16 ppb (2) N/A 9.0 μg/m3 (38) 38.0
 
March 17, 2019, noon 8.0 ppb (7) 2.0 ppb (2) 7.8 ppb (7) 6.0 ppb (6) N/A 0.0 ppb (0) 38.0 ppb (29) 0.16 ppb (2) N/A 7.0 μg/m3 (29) 29.0
 
March 17, 2019, 11 a.m. 16.0 ppb (15) 3.0 ppb (3) 15.6 ppb (14) 13.0 ppb (12) N/A 0.0 ppb (0) 33.0 ppb (25) 0.16 ppb (2) N/A 4.0 μg/m3 (17) 25.0
 
March 17, 2019, 10 a.m. 11.0 ppb (10) 2.0 ppb (2) 9.7 ppb (9) 9.0 ppb (8) N/A 0.0 ppb (0) 35.0 ppb (27) N/A N/A 6.0 μg/m3 (25) 27.0
 
March 17, 2019, 9 a.m. 5.0 ppb (5) 0.0 ppb (0) 4.3 ppb (4) 4.0 ppb (4) N/A 0.0 ppb (0) 40.0 ppb (31) 0.15 ppb (2) N/A 5.0 μg/m3 (21) 31.0
 
March 17, 2019, 8 a.m. 6.0 ppb (6) 1.0 ppb (1) 4.9 ppb (5) 5.0 ppb (5) N/A 0.0 ppb (0) N/A 0.14 ppb (2) N/A 5.0 μg/m3 (21) 21.0
 
March 17, 2019, 7 a.m. N/A N/A 4.0 ppb (4) N/A N/A 0.0 ppb (0) 39.0 ppb (30) 0.15 ppb (2) N/A 3.0 μg/m3 (12) 30.0
 
March 17, 2019, 6 a.m. N/A N/A 3.4 ppb (3) N/A N/A 0.0 ppb (0) 38.0 ppb (29) 0.15 ppb (2) N/A 4.0 μg/m3 (17) 29.0
 
March 17, 2019, 5 a.m. N/A N/A 4.3 ppb (4) N/A N/A 0.0 ppb (0) 38.0 ppb (29) 0.17 ppb (2) N/A 6.0 μg/m3 (25) 29.0
 
March 17, 2019, 4 a.m. 6.0 ppb (6) 1.0 ppb (1) 5.8 ppb (5) 6.0 ppb (6) N/A 0.0 ppb (0) 37.0 ppb (28) 0.17 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 17, 2019, 3 a.m. 6.0 ppb (6) 0.0 ppb (0) 5.5 ppb (5) 5.0 ppb (5) N/A 0.0 ppb (0) 37.0 ppb (28) 0.18 ppb (2) N/A 7.0 μg/m3 (29) 29.0
 
March 17, 2019, 2 a.m. 7.0 ppb (6) 1.0 ppb (1) 6.0 ppb (6) 6.0 ppb (6) N/A 0.0 ppb (0) 37.0 ppb (28) 0.22 ppb (2) N/A 4.0 μg/m3 (17) 28.0
 
March 17, 2019, 1 a.m. 7.0 ppb (6) 1.0 ppb (1) 6.5 ppb (6) 6.0 ppb (6) N/A 0.0 ppb (0) 38.0 ppb (29) 0.2 ppb (2) N/A 5.0 μg/m3 (21) 29.0
 
March 17, 2019, midnight 7.0 ppb (6) 1.0 ppb (1) 6.4 ppb (6) 6.0 ppb (6) N/A 0.0 ppb (0) 39.0 ppb (30) 0.19 ppb (2) N/A 6.0 μg/m3 (25) 30.0
 
March 16, 2019, 11 p.m. 10.0 ppb (9) 2.0 ppb (2) 9.6 ppb (9) 9.0 ppb (8) N/A 0.0 ppb (0) 37.0 ppb (28) 0.19 ppb (2) N/A 6.0 μg/m3 (25) 28.0
 
March 16, 2019, 10 p.m. 8.0 ppb (7) 1.0 ppb (1) 7.4 ppb (7) 7.0 ppb (6) N/A 0.0 ppb (0) 39.0 ppb (30) 0.2 ppb (2) N/A 7.0 μg/m3 (29) 30.0
 
March 16, 2019, 9 p.m. 9.0 ppb (8) 2.0 ppb (2) 8.8 ppb (8) 7.0 ppb (6) N/A 0.0 ppb (0) 39.0 ppb (30) 0.18 ppb (2) N/A 5.0 μg/m3 (21) 30.0
 
March 16, 2019, 8 p.m. 8.0 ppb (7) 2.0 ppb (2) 7.3 ppb (7) 5.0 ppb (5) N/A 0.0 ppb (0) 42.0 ppb (32) 0.18 ppb (2) N/A 7.0 μg/m3 (29) 32.0
 
March 16, 2019, 7 p.m. 5.0 ppb (5) 1.0 ppb (1) 4.7 ppb (4) 3.0 ppb (3) N/A 0.0 ppb (0) 44.0 ppb (34) 0.17 ppb (2) N/A 7.0 μg/m3 (29) 34.0
 
March 16, 2019, 6 p.m. 7.0 ppb (6) 2.0 ppb (2) 6.5 ppb (6) 5.0 ppb (5) N/A 0.0 ppb (0) 44.0 ppb (34) 0.18 ppb (2) N/A 7.0 μg/m3 (29) 34.0
 
March 16, 2019, 5 p.m. 6.0 ppb (6) 2.0 ppb (2) 5.7 ppb (5) 4.0 ppb (4) N/A 0.0 ppb (0) 42.0 ppb (32) 0.18 ppb (2) N/A 4.0 μg/m3 (17) 32.0
 
March 16, 2019, 4 p.m. 7.0 ppb (6) 2.0 ppb (2) 6.8 ppb (6) 5.0 ppb (5) N/A 0.0 ppb (0) 39.0 ppb (30) 0.19 ppb (2) N/A 4.0 μg/m3 (17) 30.0
 
March 16, 2019, 3 p.m. 7.0 ppb (6) 2.0 ppb (2) 7.3 ppb (7) 5.0 ppb (5) N/A 0.0 ppb (0) 37.0 ppb (28) 0.19 ppb (2) N/A 3.0 μg/m3 (12) 28.0
 
March 16, 2019, 2 p.m. 7.0 ppb (6) 2.0 ppb (2) 6.5 ppb (6) 5.0 ppb (5) N/A 0.0 ppb (0) 35.0 ppb (27) 0.19 ppb (2) N/A 4.0 μg/m3 (17) 27.0
 
March 16, 2019, 1 p.m. 6.0 ppb (6) 2.0 ppb (2) 6.1 ppb (6) 4.0 ppb (4) N/A 0.0 ppb (0) 33.0 ppb (25) 0.19 ppb (2) N/A 5.0 μg/m3 (21) 25.0
 
March 16, 2019, noon 8.0 ppb (7) 2.0 ppb (2) 8.1 ppb (8) 6.0 ppb (6) N/A 0.0 ppb (0) 30.0 ppb (23) 0.2 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
March 16, 2019, 11 a.m. 10.0 ppb (9) 1.0 ppb (1) 9.1 ppb (8) 8.0 ppb (7) N/A 0.0 ppb (0) 27.0 ppb (21) 0.21 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
March 16, 2019, 10 a.m. 6.0 ppb (6) 1.0 ppb (1) 5.3 ppb (5) 5.0 ppb (5) N/A N/A 29.0 ppb (22) 0.18 ppb (2) N/A 5.0 μg/m3 (21) 22.0
 
March 16, 2019, 9 a.m. 5.0 ppb (5) 0.0 ppb (0) 4.7 ppb (4) 5.0 ppb (5) N/A N/A 31.0 ppb (24) 0.16 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
March 16, 2019, 8 a.m. 9.0 ppb (8) 1.0 ppb (1) N/A 8.0 ppb (7) N/A N/A 30.0 ppb (23) 0.16 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 16, 2019, 7 a.m. 11.0 ppb (10) 2.0 ppb (2) N/A 9.0 ppb (8) N/A 0.0 ppb (0) 31.0 ppb (24) 0.19 ppb (2) N/A 8.0 μg/m3 (33) 33.0
 
March 16, 2019, 6 a.m. 15.0 ppb (14) 3.0 ppb (3) N/A 13.0 ppb (12) N/A 0.0 ppb (0) 28.0 ppb (22) 0.21 ppb (2) N/A 12.0 μg/m3 (50) 50.0
 
March 16, 2019, 5 a.m. 4.0 ppb (4) 0.0 ppb (0) N/A 4.0 ppb (4) N/A 0.0 ppb (0) 35.0 ppb (27) 0.18 ppb (2) N/A 11.0 μg/m3 (46) 46.0