ID: 2375

AQSQID: 240270006

Site Name: Howard County Near Road

Added: April 21, 2020, 6:24 p.m.

Updated: March 7, 2021, 2:32 p.m.

Location: Laurel (I 95), MD

Reporting: True, Located: True

Current AQI: 17.0

Laurel (I 95) MD, US: 39.143197, -76.846192

Date Observed (UTC) NOX NO NOY NO2 NO2Y SO2 OZONE CO PM10 PM2.5 AQI AQI/500
March 7, 2021, 1 p.m. 6.0 ppb (6) 1.5 ppb (2) N/A 4.0 ppb (4) N/A N/A N/A 0.13 ppb (2) N/A 4.0 μg/m3 (17) 17.0
 
March 7, 2021, noon 37.1 ppb (35) 21.1 ppb (20) N/A 16.0 ppb (16) N/A N/A N/A 0.21 ppb (3) N/A 5.0 μg/m3 (21) 35.0
 
March 7, 2021, 11 a.m. 46.2 ppb (44) 24.5 ppb (24) N/A 22.0 ppb (21) N/A N/A N/A 0.21 ppb (3) N/A 6.0 μg/m3 (25) 44.0
 
March 7, 2021, 10 a.m. 77.4 ppb (76) 50.8 ppb (48) N/A 27.0 ppb (26) N/A N/A N/A 0.21 ppb (3) N/A 11.0 μg/m3 (46) 76.0
 
March 7, 2021, 9 a.m. 61.7 ppb (60) 38.5 ppb (37) N/A 23.0 ppb (22) N/A N/A N/A 0.23 ppb (3) N/A 8.0 μg/m3 (34) 60.0
 
March 7, 2021, 8 a.m. 60.0 ppb (58) 36.1 ppb (35) N/A 24.0 ppb (23) N/A N/A N/A 0.27 ppb (4) N/A 7.0 μg/m3 (30) 58.0
 
March 7, 2021, 7 a.m. 43.4 ppb (41) 19.8 ppb (19) N/A 24.0 ppb (23) N/A N/A N/A 0.23 ppb (3) N/A 8.0 μg/m3 (34) 41.0
 
March 7, 2021, 6 a.m. 18.1 ppb (18) 5.2 ppb (5) N/A 13.0 ppb (13) N/A N/A N/A 0.2 ppb (3) N/A 8.0 μg/m3 (34) 34.0
 
March 7, 2021, 5 a.m. 25.6 ppb (25) 8.4 ppb (8) N/A 17.0 ppb (17) N/A N/A N/A 0.22 ppb (3) N/A 11.0 μg/m3 (46) 46.0
 
March 7, 2021, 4 a.m. 18.5 ppb (18) 7.3 ppb (7) N/A 11.0 ppb (11) N/A N/A N/A N/A N/A 10.0 μg/m3 (42) 42.0
 
March 7, 2021, 3 a.m. 19.7 ppb (19) 9.6 ppb (10) N/A 10.0 ppb (10) N/A N/A N/A 0.17 ppb (3) N/A 6.0 μg/m3 (25) 25.0
 
March 7, 2021, 2 a.m. 15.4 ppb (15) 2.9 ppb (3) N/A 13.0 ppb (13) N/A N/A N/A 0.17 ppb (3) N/A 8.0 μg/m3 (34) 34.0
 
March 7, 2021, 1 a.m. 17.1 ppb (17) 3.0 ppb (3) N/A 14.0 ppb (14) N/A N/A N/A 0.17 ppb (3) N/A 11.0 μg/m3 (46) 46.0
 
March 7, 2021, midnight 13.2 ppb (13) 2.6 ppb (3) N/A 11.0 ppb (11) N/A N/A N/A 0.15 ppb (2) N/A 4.0 μg/m3 (17) 17.0
 
March 6, 2021, 11 p.m. 13.8 ppb (14) 2.6 ppb (3) N/A 11.0 ppb (11) N/A N/A N/A 0.14 ppb (2) N/A 5.0 μg/m3 (21) 21.0
 
March 6, 2021, 10 p.m. 5.5 ppb (6) 1.5 ppb (2) N/A 4.0 ppb (4) N/A N/A N/A 0.13 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
March 6, 2021, 9 p.m. 5.7 ppb (6) 1.8 ppb (2) N/A 4.0 ppb (4) N/A N/A N/A 0.13 ppb (2) N/A 4.0 μg/m3 (17) 17.0
 
March 6, 2021, 8 p.m. 3.7 ppb (4) 1.2 ppb (2) N/A 2.0 ppb (2) N/A N/A N/A 0.12 ppb (2) N/A 4.0 μg/m3 (17) 17.0
 
March 6, 2021, 7 p.m. 5.6 ppb (6) 2.5 ppb (3) N/A 3.0 ppb (3) N/A N/A N/A 0.12 ppb (2) N/A 4.0 μg/m3 (17) 17.0
 
March 6, 2021, 6 p.m. 4.5 ppb (5) 1.8 ppb (2) N/A 3.0 ppb (3) N/A N/A N/A 0.12 ppb (2) N/A 3.0 μg/m3 (13) 13.0
 
March 6, 2021, 5 p.m. 3.7 ppb (4) 1.5 ppb (2) N/A 2.0 ppb (2) N/A N/A N/A 0.13 ppb (2) N/A 4.0 μg/m3 (17) 17.0
 
March 6, 2021, 4 p.m. 3.4 ppb (4) 1.2 ppb (2) N/A 2.0 ppb (2) N/A N/A N/A 0.13 ppb (2) N/A 4.0 μg/m3 (17) 17.0
 
March 6, 2021, 3 p.m. 3.2 ppb (4) 1.0 ppb (1) N/A 2.0 ppb (2) N/A N/A N/A 0.13 ppb (2) N/A 3.0 μg/m3 (13) 13.0
 
March 6, 2021, 2 p.m. 4.0 ppb (4) 1.2 ppb (2) N/A 3.0 ppb (3) N/A N/A N/A 0.14 ppb (2) N/A 4.0 μg/m3 (17) 17.0
 
March 6, 2021, 1 p.m. 7.4 ppb (7) 2.6 ppb (3) N/A 5.0 ppb (5) N/A N/A N/A 0.14 ppb (2) N/A 2.0 μg/m3 (9) 9.0
 
March 6, 2021, noon 21.9 ppb (21) 8.6 ppb (9) N/A 13.0 ppb (13) N/A N/A N/A 0.18 ppb (3) N/A 5.0 μg/m3 (21) 21.0
 
March 6, 2021, 11 a.m. 32.0 ppb (31) 12.7 ppb (12) N/A 19.0 ppb (18) N/A N/A N/A 0.2 ppb (3) N/A 5.0 μg/m3 (21) 31.0
 
March 6, 2021, 10 a.m. 28.4 ppb (27) 8.1 ppb (8) N/A 20.0 ppb (19) N/A N/A N/A 0.2 ppb (3) N/A 4.0 μg/m3 (17) 27.0
 
March 6, 2021, 9 a.m. 24.1 ppb (23) 9.2 ppb (9) N/A 15.0 ppb (15) N/A N/A N/A 0.16 ppb (3) N/A 5.0 μg/m3 (21) 23.0
 
March 6, 2021, 8 a.m. 38.3 ppb (37) 17.8 ppb (17) N/A 20.0 ppb (19) N/A N/A N/A 0.21 ppb (3) N/A 3.0 μg/m3 (13) 37.0
 
March 6, 2021, 7 a.m. 54.3 ppb (52) 25.8 ppb (25) N/A 28.0 ppb (27) N/A N/A N/A 0.23 ppb (3) N/A 1.0 μg/m3 (5) 52.0
 
March 6, 2021, 6 a.m. 21.4 ppb (21) 8.5 ppb (9) N/A 13.0 ppb (13) N/A N/A N/A 0.14 ppb (2) N/A 1.0 μg/m3 (5) 21.0
 
March 6, 2021, 5 a.m. 6.1 ppb (6) 1.9 ppb (2) N/A 4.0 ppb (4) N/A N/A N/A 0.14 ppb (2) N/A 3.0 μg/m3 (13) 13.0
 
March 6, 2021, 4 a.m. 11.3 ppb (11) 3.8 ppb (4) N/A 7.0 ppb (7) N/A N/A N/A N/A N/A 2.0 μg/m3 (9) 11.0
 
March 6, 2021, 3 a.m. 31.5 ppb (30) 16.5 ppb (16) N/A 15.0 ppb (15) N/A N/A N/A 0.21 ppb (3) N/A 4.0 μg/m3 (17) 30.0
 
March 6, 2021, 2 a.m. 38.8 ppb (37) 18.8 ppb (18) N/A 20.0 ppb (19) N/A N/A N/A 0.23 ppb (3) N/A 6.0 μg/m3 (25) 37.0
 
March 6, 2021, 1 a.m. 33.0 ppb (32) 15.8 ppb (15) N/A 17.0 ppb (17) N/A N/A N/A 0.23 ppb (3) N/A 5.0 μg/m3 (21) 32.0
 
March 6, 2021, midnight 10.0 ppb (10) 2.5 ppb (3) N/A 7.0 ppb (7) N/A N/A N/A 0.2 ppb (3) N/A 4.0 μg/m3 (17) 17.0
 
March 5, 2021, 11 p.m. 5.7 ppb (6) 1.2 ppb (2) N/A 4.0 ppb (4) N/A N/A N/A 0.18 ppb (3) N/A 4.0 μg/m3 (17) 17.0
 
March 5, 2021, 10 p.m. 6.8 ppb (7) 2.0 ppb (2) N/A 5.0 ppb (5) N/A N/A N/A 0.18 ppb (3) N/A 5.0 μg/m3 (21) 21.0
 
March 5, 2021, 9 p.m. 3.3 ppb (4) 0.8 ppb (1) N/A 2.0 ppb (2) N/A N/A N/A 0.17 ppb (3) N/A 6.0 μg/m3 (25) 25.0
 
March 5, 2021, 8 p.m. 3.0 ppb (3) 0.9 ppb (1) N/A 2.0 ppb (2) N/A N/A N/A 0.17 ppb (3) N/A 1.0 μg/m3 (5) 5.0
 
March 5, 2021, 7 p.m. 2.4 ppb (3) 0.8 ppb (1) N/A 2.0 ppb (2) N/A N/A N/A 0.17 ppb (3) N/A 1.0 μg/m3 (5) 5.0
 
March 5, 2021, 6 p.m. N/A N/A N/A N/A N/A N/A N/A 0.16 ppb (3) N/A 1.0 μg/m3 (5) 5.0
 
March 5, 2021, 5 p.m. N/A N/A N/A N/A N/A N/A N/A 0.16 ppb (3) N/A 1.0 μg/m3 (5) 5.0
 
March 5, 2021, 4 p.m. 2.3 ppb (3) 0.9 ppb (1) N/A 1.0 ppb (1) N/A N/A N/A 0.15 ppb (2) N/A 2.0 μg/m3 (9) 9.0
 
March 5, 2021, 3 p.m. 2.4 ppb (3) 0.9 ppb (1) N/A 2.0 ppb (2) N/A N/A N/A 0.15 ppb (2) N/A 0.0 μg/m3 (0) 3.0
 
March 5, 2021, 2 p.m. 5.1 ppb (5) 2.2 ppb (3) N/A 3.0 ppb (3) N/A N/A N/A 0.15 ppb (2) N/A 1.0 μg/m3 (5) 5.0
 
March 5, 2021, 1 p.m. 4.6 ppb (5) 1.6 ppb (2) N/A 3.0 ppb (3) N/A N/A N/A 0.15 ppb (2) N/A 3.0 μg/m3 (13) 13.0
 
March 5, 2021, noon 6.6 ppb (7) 2.5 ppb (3) N/A 4.0 ppb (4) N/A N/A N/A 0.16 ppb (3) N/A 4.0 μg/m3 (17) 17.0
 
March 5, 2021, 11 a.m. 13.2 ppb (13) 5.4 ppb (6) N/A 8.0 ppb (8) N/A N/A N/A 0.16 ppb (3) N/A 3.0 μg/m3 (13) 13.0
 
March 5, 2021, 10 a.m. 15.5 ppb (15) 5.7 ppb (6) N/A 10.0 ppb (10) N/A N/A N/A 0.16 ppb (3) N/A 2.0 μg/m3 (9) 15.0
 
March 5, 2021, 9 a.m. 11.2 ppb (11) 3.1 ppb (3) N/A 8.0 ppb (8) N/A N/A N/A 0.15 ppb (2) N/A 4.0 μg/m3 (17) 17.0
 
March 5, 2021, 8 a.m. N/A N/A N/A N/A N/A N/A N/A 0.15 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
March 5, 2021, 7 a.m. 12.4 ppb (12) 3.7 ppb (4) N/A 9.0 ppb (9) N/A N/A N/A 0.16 ppb (3) N/A 3.0 μg/m3 (13) 13.0
 
March 5, 2021, 6 a.m. 8.9 ppb (9) 2.6 ppb (3) N/A 6.0 ppb (6) N/A N/A N/A 0.15 ppb (2) N/A 4.0 μg/m3 (17) 17.0
 
March 5, 2021, 5 a.m. 9.8 ppb (10) 3.0 ppb (3) N/A 7.0 ppb (7) N/A N/A N/A 0.16 ppb (3) N/A 8.0 μg/m3 (34) 34.0
 
March 5, 2021, 4 a.m. 8.7 ppb (9) 3.0 ppb (3) N/A 6.0 ppb (6) N/A N/A N/A N/A N/A 2.0 μg/m3 (9) 9.0
 
March 5, 2021, 3 a.m. 8.8 ppb (9) 3.1 ppb (3) N/A 6.0 ppb (6) N/A N/A N/A 0.18 ppb (3) N/A 0.0 μg/m3 (0) 9.0
 
March 5, 2021, 2 a.m. 9.3 ppb (9) 3.6 ppb (4) N/A 6.0 ppb (6) N/A N/A N/A 0.18 ppb (3) N/A 0.0 μg/m3 (0) 9.0
 
March 5, 2021, 1 a.m. 7.8 ppb (8) 2.7 ppb (3) N/A 5.0 ppb (5) N/A N/A N/A 0.18 ppb (3) N/A 0.0 μg/m3 (0) 8.0
 
March 5, 2021, midnight 6.2 ppb (6) 1.6 ppb (2) N/A 5.0 ppb (5) N/A N/A N/A 0.16 ppb (3) N/A 2.0 μg/m3 (9) 9.0
 
March 4, 2021, 11 p.m. 9.9 ppb (10) 3.0 ppb (3) N/A 7.0 ppb (7) N/A N/A N/A 0.15 ppb (2) N/A 4.0 μg/m3 (17) 17.0
 
March 4, 2021, 10 p.m. 5.7 ppb (6) 1.3 ppb (2) N/A 4.0 ppb (4) N/A N/A N/A 0.16 ppb (3) N/A 4.0 μg/m3 (17) 17.0
 
March 4, 2021, 9 p.m. 4.1 ppb (4) 1.0 ppb (1) N/A 3.0 ppb (3) N/A N/A N/A 0.16 ppb (3) N/A 2.0 μg/m3 (9) 9.0
 
March 4, 2021, 8 p.m. 3.7 ppb (4) 0.9 ppb (1) N/A 3.0 ppb (3) N/A N/A N/A 0.16 ppb (3) N/A 4.0 μg/m3 (17) 17.0
 
March 4, 2021, 7 p.m. 3.5 ppb (4) 0.9 ppb (1) N/A 3.0 ppb (3) N/A N/A N/A 0.16 ppb (3) N/A 6.0 μg/m3 (25) 25.0
 
March 4, 2021, 6 p.m. 4.7 ppb (5) 1.5 ppb (2) N/A 3.0 ppb (3) N/A N/A N/A 0.16 ppb (3) N/A 6.0 μg/m3 (25) 25.0
 
March 4, 2021, 5 p.m. 4.0 ppb (4) 1.1 ppb (2) N/A 3.0 ppb (3) N/A N/A N/A 0.17 ppb (3) N/A 4.0 μg/m3 (17) 17.0
 
March 4, 2021, 4 p.m. 4.9 ppb (5) 1.7 ppb (2) N/A 3.0 ppb (3) N/A N/A N/A 0.15 ppb (2) N/A 5.0 μg/m3 (21) 21.0
 
March 4, 2021, 3 p.m. 4.0 ppb (4) 1.2 ppb (2) N/A 3.0 ppb (3) N/A N/A N/A 0.15 ppb (2) N/A 6.0 μg/m3 (25) 25.0
 
March 4, 2021, 2 p.m. 5.3 ppb (5) 1.6 ppb (2) N/A 4.0 ppb (4) N/A N/A N/A 0.15 ppb (2) N/A 7.0 μg/m3 (30) 30.0
 
March 4, 2021, 1 p.m. 7.5 ppb (8) 3.1 ppb (3) N/A 4.0 ppb (4) N/A N/A N/A 0.17 ppb (3) N/A 6.0 μg/m3 (25) 25.0
 
March 4, 2021, noon 10.9 ppb (11) 2.6 ppb (3) N/A 8.0 ppb (8) N/A N/A N/A 0.17 ppb (3) N/A 9.0 μg/m3 (38) 38.0
 
March 4, 2021, 11 a.m. 30.9 ppb (30) 13.4 ppb (13) N/A 18.0 ppb (17) N/A N/A N/A 0.23 ppb (3) N/A 9.0 μg/m3 (38) 38.0
 
March 4, 2021, 10 a.m. 43.7 ppb (42) 23.5 ppb (23) N/A 20.0 ppb (19) N/A N/A N/A 0.2 ppb (3) N/A 6.0 μg/m3 (25) 42.0
 
March 4, 2021, 9 a.m. 33.2 ppb (32) 14.2 ppb (14) N/A 19.0 ppb (18) N/A N/A N/A 0.24 ppb (3) N/A 5.0 μg/m3 (21) 32.0
 
March 4, 2021, 8 a.m. 71.5 ppb (70) 38.5 ppb (37) N/A 33.0 ppb (32) N/A N/A N/A 0.25 ppb (3) N/A 6.0 μg/m3 (25) 70.0
 
March 4, 2021, 7 a.m. 60.5 ppb (58) 30.2 ppb (29) N/A 30.0 ppb (29) N/A N/A N/A 0.24 ppb (3) N/A 9.0 μg/m3 (38) 58.0
 
March 4, 2021, 6 a.m. 41.0 ppb (39) 13.7 ppb (13) N/A 27.0 ppb (26) N/A N/A N/A 0.31 ppb (4) N/A 6.0 μg/m3 (25) 39.0
 
March 4, 2021, 5 a.m. 32.4 ppb (31) 12.2 ppb (12) N/A 20.0 ppb (19) N/A N/A N/A 0.23 ppb (3) N/A 4.0 μg/m3 (17) 31.0
 
March 4, 2021, 4 a.m. 61.7 ppb (60) 31.4 ppb (30) N/A 30.0 ppb (29) N/A N/A N/A 0.34 ppb (4) N/A 4.0 μg/m3 (17) 60.0
 
March 4, 2021, 3 a.m. 95.8 ppb (96) 59.6 ppb (57) N/A 36.0 ppb (34) N/A N/A N/A 0.25 ppb (3) N/A 5.0 μg/m3 (21) 96.0
 
March 4, 2021, 2 a.m. 84.0 ppb (83) 48.9 ppb (47) N/A 35.0 ppb (34) N/A N/A N/A 0.33 ppb (4) N/A 8.0 μg/m3 (34) 83.0
 
March 4, 2021, 1 a.m. 40.2 ppb (38) 21.5 ppb (21) N/A 19.0 ppb (18) N/A N/A N/A 0.21 ppb (3) N/A 5.0 μg/m3 (21) 38.0
 
March 4, 2021, midnight 33.8 ppb (32) 15.8 ppb (15) N/A 18.0 ppb (17) N/A N/A N/A 0.17 ppb (3) N/A 3.0 μg/m3 (13) 32.0
 
March 3, 2021, 11 p.m. 29.2 ppb (28) 12.2 ppb (12) N/A 17.0 ppb (17) N/A N/A N/A 0.17 ppb (3) N/A 4.0 μg/m3 (17) 28.0
 
March 3, 2021, 10 p.m. 18.3 ppb (18) 6.1 ppb (6) N/A 12.0 ppb (12) N/A N/A N/A 0.14 ppb (2) N/A 0.0 μg/m3 (0) 18.0
 
March 3, 2021, 9 p.m. 12.1 ppb (12) 4.9 ppb (5) N/A 7.0 ppb (7) N/A N/A N/A 0.11 ppb (2) N/A -2.0 μg/m3 (0) 12.0
 
March 3, 2021, 8 p.m. 15.6 ppb (15) 7.5 ppb (8) N/A 8.0 ppb (8) N/A N/A N/A 0.12 ppb (2) N/A 2.0 μg/m3 (9) 15.0
 
March 3, 2021, 7 p.m. 13.1 ppb (13) 6.7 ppb (7) N/A 6.0 ppb (6) N/A N/A N/A 0.11 ppb (2) N/A 2.0 μg/m3 (9) 13.0
 
March 3, 2021, 6 p.m. 10.8 ppb (11) 5.1 ppb (5) N/A 6.0 ppb (6) N/A N/A N/A 0.09 ppb (2) N/A 0.0 μg/m3 (0) 11.0
 
March 3, 2021, 5 p.m. 12.2 ppb (12) 5.9 ppb (6) N/A 6.0 ppb (6) N/A N/A N/A 0.1 ppb (2) N/A 3.0 μg/m3 (13) 13.0
 
March 3, 2021, 4 p.m. 10.6 ppb (10) 4.8 ppb (5) N/A 6.0 ppb (6) N/A N/A N/A 0.1 ppb (2) N/A 5.0 μg/m3 (21) 21.0
 
March 3, 2021, 3 p.m. 8.2 ppb (8) 3.2 ppb (4) N/A 5.0 ppb (5) N/A N/A N/A 0.1 ppb (2) N/A 4.0 μg/m3 (17) 17.0
 
March 3, 2021, 2 p.m. 34.6 ppb (33) 19.0 ppb (18) N/A 16.0 ppb (16) N/A N/A N/A 0.19 ppb (3) N/A 6.0 μg/m3 (25) 33.0
 
March 3, 2021, 1 p.m. 54.0 ppb (51) 31.5 ppb (30) N/A 23.0 ppb (22) N/A N/A N/A 0.28 ppb (4) N/A 6.0 μg/m3 (25) 51.0
 
March 3, 2021, noon 84.6 ppb (84) 51.3 ppb (49) N/A 33.0 ppb (32) N/A N/A N/A 0.33 ppb (4) N/A 6.0 μg/m3 (25) 84.0
 
March 3, 2021, 11 a.m. 138.6 ppb (109) 94.6 ppb (95) N/A 44.0 ppb (42) N/A N/A N/A 0.26 ppb (4) N/A 6.0 μg/m3 (25) 109.0
 
March 3, 2021, 10 a.m. 156.2 ppb (112) 120.7 ppb (105) N/A 35.0 ppb (34) N/A N/A N/A 0.21 ppb (3) N/A 6.0 μg/m3 (25) 112.0
 
March 3, 2021, 9 a.m. 247.2 ppb (129) 195.7 ppb (119) N/A 51.0 ppb (49) N/A N/A N/A 0.26 ppb (4) N/A 9.0 μg/m3 (38) 129.0
 
March 3, 2021, 8 a.m. N/A N/A N/A N/A N/A N/A N/A 0.46 ppb (6) N/A 15.0 μg/m3 (58) 58.0
 
March 3, 2021, 7 a.m. 157.9 ppb (112) 112.1 ppb (104) N/A 46.0 ppb (44) N/A N/A N/A 0.4 ppb (5) N/A 7.0 μg/m3 (30) 112.0
 
March 3, 2021, 6 a.m. 160.8 ppb (113) 117.2 ppb (105) N/A 44.0 ppb (42) N/A N/A N/A 0.49 ppb (6) N/A 8.0 μg/m3 (34) 113.0
 
March 3, 2021, 5 a.m. 157.5 ppb (112) 110.2 ppb (103) N/A 47.0 ppb (45) N/A N/A N/A 0.57 ppb (7) N/A 7.0 μg/m3 (30) 112.0
 
March 3, 2021, 4 a.m. 216.8 ppb (123) 170.8 ppb (115) N/A 46.0 ppb (44) N/A N/A N/A N/A N/A 9.0 μg/m3 (38) 123.0
 
March 3, 2021, 3 a.m. 222.8 ppb (125) 176.4 ppb (116) N/A 46.0 ppb (44) N/A N/A N/A 0.6 ppb (7) N/A 10.0 μg/m3 (42) 125.0
 
March 3, 2021, 2 a.m. 210.0 ppb (122) 167.1 ppb (114) N/A 43.0 ppb (41) N/A N/A N/A 0.54 ppb (6) N/A 9.0 μg/m3 (38) 122.0
 
March 3, 2021, 1 a.m. 245.8 ppb (129) 200.2 ppb (120) N/A 46.0 ppb (44) N/A N/A N/A 0.39 ppb (5) N/A 6.0 μg/m3 (25) 129.0
 
March 3, 2021, midnight 198.3 ppb (120) 162.1 ppb (113) N/A 36.0 ppb (34) N/A N/A N/A 0.34 ppb (4) N/A 2.0 μg/m3 (9) 120.0
 
March 2, 2021, 11 p.m. 221.2 ppb (124) 175.6 ppb (116) N/A N/A N/A N/A N/A 0.29 ppb (4) N/A 3.0 μg/m3 (13) 124.0
 
March 2, 2021, 10 p.m. 23.4 ppb (23) 9.5 ppb (9) N/A 14.0 ppb (14) N/A N/A N/A 0.26 ppb (4) N/A 1.0 μg/m3 (5) 23.0
 
March 2, 2021, 9 p.m. 5.5 ppb (6) 1.7 ppb (2) N/A 4.0 ppb (4) N/A N/A N/A 0.23 ppb (3) N/A 2.0 μg/m3 (9) 9.0
 
March 2, 2021, 8 p.m. 5.8 ppb (6) 2.4 ppb (3) N/A 3.0 ppb (3) N/A N/A N/A 0.24 ppb (3) N/A 1.0 μg/m3 (5) 6.0
 
March 2, 2021, 7 p.m. 8.8 ppb (9) 4.4 ppb (5) N/A 4.0 ppb (4) N/A N/A N/A 0.24 ppb (3) N/A -1.0 μg/m3 (0) 9.0
 
March 2, 2021, 6 p.m. 4.6 ppb (5) 1.7 ppb (2) N/A 3.0 ppb (3) N/A N/A N/A 0.23 ppb (3) N/A 0.0 μg/m3 (0) 5.0
 
March 2, 2021, 5 p.m. 4.6 ppb (5) 2.0 ppb (2) N/A 3.0 ppb (3) N/A N/A N/A 0.23 ppb (3) N/A 1.0 μg/m3 (5) 5.0
 
March 2, 2021, 4 p.m. 4.5 ppb (5) 1.8 ppb (2) N/A 3.0 ppb (3) N/A N/A N/A 0.21 ppb (3) N/A N/A 5.0
 
March 2, 2021, 3 p.m. 4.8 ppb (5) 1.8 ppb (2) N/A 3.0 ppb (3) N/A N/A N/A 0.21 ppb (3) N/A 1.0 μg/m3 (5) 5.0
 
March 2, 2021, 2 p.m. 4.8 ppb (5) 2.1 ppb (2) N/A 3.0 ppb (3) N/A N/A N/A 0.21 ppb (3) N/A 3.0 μg/m3 (13) 13.0
 
March 2, 2021, 1 p.m. 8.4 ppb (8) 3.2 ppb (4) N/A 5.0 ppb (5) N/A N/A N/A 0.21 ppb (3) N/A 1.0 μg/m3 (5) 8.0
 
March 2, 2021, noon 16.1 ppb (16) 5.7 ppb (6) N/A 10.0 ppb (10) N/A N/A N/A 0.22 ppb (3) N/A 1.0 μg/m3 (5) 16.0
 
March 2, 2021, 11 a.m. 18.7 ppb (18) 6.4 ppb (7) N/A 12.0 ppb (12) N/A N/A N/A 0.21 ppb (3) N/A 5.0 μg/m3 (21) 21.0
 
March 2, 2021, 10 a.m. 23.1 ppb (22) 8.6 ppb (9) N/A 15.0 ppb (15) N/A N/A N/A 0.22 ppb (3) N/A 2.0 μg/m3 (9) 22.0
 
March 2, 2021, 9 a.m. 15.6 ppb (15) 5.6 ppb (6) N/A 10.0 ppb (10) N/A N/A N/A 0.21 ppb (3) N/A 1.0 μg/m3 (5) 15.0
 
March 2, 2021, 8 a.m. 22.8 ppb (22) 9.4 ppb (9) N/A 13.0 ppb (13) N/A N/A N/A 0.17 ppb (3) N/A 1.0 μg/m3 (5) 22.0
 
March 2, 2021, 7 a.m. 16.7 ppb (16) 5.4 ppb (6) N/A 11.0 ppb (11) N/A N/A N/A N/A N/A 4.0 μg/m3 (17) 17.0
 
March 2, 2021, 6 a.m. 16.4 ppb (16) 7.5 ppb (8) N/A 9.0 ppb (9) N/A N/A N/A 0.17 ppb (3) N/A 6.0 μg/m3 (25) 25.0
 
March 2, 2021, 5 a.m. 7.7 ppb (8) 2.6 ppb (3) N/A 5.0 ppb (5) N/A N/A N/A 0.17 ppb (3) N/A 4.0 μg/m3 (17) 17.0
 
March 2, 2021, 4 a.m. 7.9 ppb (8) 2.3 ppb (3) N/A 6.0 ppb (6) N/A N/A N/A N/A N/A 1.0 μg/m3 (5) 8.0
 
March 2, 2021, 3 a.m. 8.8 ppb (9) 3.0 ppb (3) N/A 6.0 ppb (6) N/A N/A N/A 0.24 ppb (3) N/A 0.0 μg/m3 (0) 9.0
 
March 2, 2021, 2 a.m. 8.5 ppb (9) 2.9 ppb (3) N/A 6.0 ppb (6) N/A N/A N/A 0.25 ppb (3) N/A 2.0 μg/m3 (9) 9.0
 
March 2, 2021, 1 a.m. 15.1 ppb (15) 6.2 ppb (6) N/A 9.0 ppb (9) N/A N/A N/A 0.25 ppb (3) N/A 5.0 μg/m3 (21) 21.0
 
March 2, 2021, midnight 15.3 ppb (15) 6.2 ppb (6) N/A 9.0 ppb (9) N/A N/A N/A 0.23 ppb (3) N/A 5.0 μg/m3 (21) 21.0
 
March 1, 2021, 11 p.m. 9.0 ppb (9) 3.1 ppb (3) N/A 6.0 ppb (6) N/A N/A N/A 0.23 ppb (3) N/A 4.0 μg/m3 (17) 17.0
 
March 1, 2021, 10 p.m. 10.9 ppb (11) 4.0 ppb (4) N/A 7.0 ppb (7) N/A N/A N/A 0.24 ppb (3) N/A 6.0 μg/m3 (25) 25.0
 
March 1, 2021, 9 p.m. 14.5 ppb (14) 6.4 ppb (7) N/A 8.0 ppb (8) N/A N/A N/A 0.27 ppb (4) N/A 3.0 μg/m3 (13) 14.0
 
March 1, 2021, 8 p.m. 17.9 ppb (17) 8.5 ppb (9) N/A 9.0 ppb (9) N/A N/A N/A 0.28 ppb (4) N/A 6.0 μg/m3 (25) 25.0
 
March 1, 2021, 7 p.m. 6.4 ppb (7) 1.8 ppb (2) N/A 5.0 ppb (5) N/A N/A N/A 0.24 ppb (3) N/A 10.0 μg/m3 (42) 42.0
 
March 1, 2021, 6 p.m. 6.7 ppb (7) 2.2 ppb (3) N/A 4.0 ppb (4) N/A N/A N/A 0.23 ppb (3) N/A 4.0 μg/m3 (17) 17.0
 
March 1, 2021, 5 p.m. 6.7 ppb (7) 1.8 ppb (2) N/A 5.0 ppb (5) N/A N/A N/A 0.24 ppb (3) N/A 3.0 μg/m3 (13) 13.0
 
March 1, 2021, 4 p.m. 11.4 ppb (11) 3.2 ppb (4) N/A 8.0 ppb (8) N/A N/A N/A 0.26 ppb (4) N/A 5.0 μg/m3 (21) 21.0
 
March 1, 2021, 3 p.m. 71.0 ppb (70) 48.2 ppb (46) N/A 23.0 ppb (22) N/A N/A N/A 0.5 ppb (6) N/A 5.0 μg/m3 (21) 70.0
 
March 1, 2021, 2 p.m. 60.6 ppb (59) 39.7 ppb (38) N/A 21.0 ppb (20) N/A N/A N/A 0.49 ppb (6) N/A 5.0 μg/m3 (21) 59.0
 
March 1, 2021, 1 p.m. 101.0 ppb (101) 75.3 ppb (74) N/A 26.0 ppb (25) N/A N/A N/A 0.64 ppb (7) N/A 6.0 μg/m3 (25) 101.0
 
March 1, 2021, noon 53.6 ppb (51) 34.1 ppb (33) N/A 20.0 ppb (19) N/A N/A N/A 0.47 ppb (6) N/A 4.0 μg/m3 (17) 51.0
 
March 1, 2021, 11 a.m. 50.9 ppb (49) 31.9 ppb (31) N/A 19.0 ppb (18) N/A N/A N/A 0.43 ppb (5) N/A 2.0 μg/m3 (9) 49.0
 
March 1, 2021, 10 a.m. 41.9 ppb (40) 25.2 ppb (24) N/A 17.0 ppb (17) N/A N/A N/A 0.41 ppb (5) N/A 4.0 μg/m3 (17) 40.0
 
March 1, 2021, 9 a.m. 39.0 ppb (37) 21.3 ppb (21) N/A 18.0 ppb (17) N/A N/A N/A 0.39 ppb (5) N/A 3.0 μg/m3 (13) 37.0
 
March 1, 2021, 8 a.m. N/A N/A N/A N/A N/A N/A N/A 0.31 ppb (4) N/A 0.0 μg/m3 (0) 4.0
 
March 1, 2021, 7 a.m. 36.9 ppb (35) 17.2 ppb (17) N/A 20.0 ppb (19) N/A N/A N/A 0.32 ppb (4) N/A 5.0 μg/m3 (21) 35.0
 
March 1, 2021, 6 a.m. 31.9 ppb (31) 10.4 ppb (10) N/A 21.0 ppb (20) N/A N/A N/A 0.34 ppb (4) N/A 9.0 μg/m3 (38) 38.0
 
March 1, 2021, 5 a.m. 34.8 ppb (33) 13.1 ppb (13) N/A 22.0 ppb (21) N/A N/A N/A 0.34 ppb (4) N/A 4.0 μg/m3 (17) 33.0
 
March 1, 2021, 4 a.m. 42.1 ppb (40) 18.6 ppb (18) N/A 24.0 ppb (23) N/A N/A N/A N/A N/A 6.0 μg/m3 (25) 40.0
 
March 1, 2021, 3 a.m. 29.7 ppb (29) 10.6 ppb (10) N/A 19.0 ppb (18) N/A N/A N/A 0.22 ppb (3) N/A 8.0 μg/m3 (34) 34.0
 
March 1, 2021, 2 a.m. 23.4 ppb (23) 7.4 ppb (7) N/A 16.0 ppb (16) N/A N/A N/A 0.2 ppb (3) N/A 9.0 μg/m3 (38) 38.0
 
March 1, 2021, 1 a.m. 32.3 ppb (31) 11.4 ppb (11) N/A 21.0 ppb (20) N/A N/A N/A 0.22 ppb (3) N/A 10.0 μg/m3 (42) 42.0
 
March 1, 2021, midnight 33.6 ppb (32) 14.0 ppb (14) N/A 20.0 ppb (19) N/A N/A N/A 0.27 ppb (4) N/A 8.0 μg/m3 (34) 34.0
 
Feb. 28, 2021, 11 p.m. 29.7 ppb (29) 12.0 ppb (12) N/A 18.0 ppb (17) N/A N/A N/A 0.25 ppb (3) N/A 6.0 μg/m3 (25) 29.0
 
Feb. 28, 2021, 10 p.m. 28.8 ppb (28) 12.5 ppb (12) N/A 16.0 ppb (16) N/A N/A N/A 0.23 ppb (3) N/A 3.0 μg/m3 (13) 28.0
 
Feb. 28, 2021, 9 p.m. 23.9 ppb (23) 10.7 ppb (11) N/A 13.0 ppb (13) N/A N/A N/A 0.22 ppb (3) N/A 3.0 μg/m3 (13) 23.0
 
Feb. 28, 2021, 8 p.m. 23.6 ppb (23) 10.4 ppb (10) N/A 13.0 ppb (13) N/A N/A N/A 0.18 ppb (3) N/A 3.0 μg/m3 (13) 23.0
 
Feb. 28, 2021, 7 p.m. 19.9 ppb (19) 8.7 ppb (9) N/A 11.0 ppb (11) N/A N/A N/A 0.17 ppb (3) N/A 3.0 μg/m3 (13) 19.0
 
Feb. 28, 2021, 6 p.m. 20.4 ppb (20) 9.5 ppb (9) N/A 11.0 ppb (11) N/A N/A N/A 0.16 ppb (3) N/A 6.0 μg/m3 (25) 25.0
 
Feb. 28, 2021, 5 p.m. 23.3 ppb (22) 11.2 ppb (11) N/A 12.0 ppb (12) N/A N/A N/A 0.17 ppb (3) N/A 8.0 μg/m3 (34) 34.0
 
Feb. 28, 2021, 4 p.m. 26.7 ppb (26) 11.7 ppb (12) N/A 15.0 ppb (15) N/A N/A N/A 0.2 ppb (3) N/A 11.0 μg/m3 (46) 46.0
 
Feb. 28, 2021, 3 p.m. 30.6 ppb (29) 14.1 ppb (14) N/A 16.0 ppb (16) N/A N/A N/A 0.25 ppb (3) N/A 9.0 μg/m3 (38) 38.0
 
Feb. 28, 2021, 2 p.m. 31.3 ppb (30) 14.0 ppb (14) N/A 17.0 ppb (17) N/A N/A N/A 0.25 ppb (3) N/A 10.0 μg/m3 (42) 42.0