ID: 7720

AQSQID: 840250170010

Site Name: Chelmsfordnr

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

Updated: Feb. 26, 2021, 4:32 p.m.

Location: Chelmsford (E Chelmsford), MA

Reporting: True, Located: True

Current AQI: 38.0

Chelmsford (E Chelmsford) MA, US: 42.612113, -71.307519

Date Observed (UTC) NOX NO NOY NO2 NO2Y SO2 OZONE CO PM10 PM2.5 AQI AQI/500
Feb. 26, 2021, 2 p.m. 4.0 ppb (4) 1.0 ppb (1) N/A 3.0 ppb (3) N/A N/A 41.0 ppb (38) N/A N/A 3.0 μg/m3 (13) 38.0
 
Feb. 26, 2021, 1 p.m. 7.0 ppb (7) 2.0 ppb (2) N/A 5.0 ppb (5) N/A N/A 38.0 ppb (36) N/A N/A 4.0 μg/m3 (17) 36.0
 
Feb. 26, 2021, noon 17.0 ppb (17) 2.0 ppb (2) N/A 14.0 ppb (14) N/A N/A 27.0 ppb (25) N/A N/A 5.0 μg/m3 (21) 25.0
 
Feb. 26, 2021, 11 a.m. 26.0 ppb (25) 2.0 ppb (2) N/A 24.0 ppb (23) N/A N/A 17.0 ppb (16) N/A N/A 4.0 μg/m3 (17) 25.0
 
Feb. 26, 2021, 10 a.m. 15.0 ppb (15) 1.0 ppb (1) N/A 14.0 ppb (14) N/A N/A 27.0 ppb (25) N/A N/A 3.0 μg/m3 (13) 25.0
 
Feb. 26, 2021, 9 a.m. 33.0 ppb (32) 8.0 ppb (8) N/A 25.0 ppb (24) N/A N/A 20.0 ppb (19) N/A N/A 4.0 μg/m3 (17) 32.0
 
Feb. 26, 2021, 8 a.m. 9.0 ppb (9) 2.0 ppb (2) N/A 7.0 ppb (7) N/A N/A 36.0 ppb (34) N/A N/A 3.0 μg/m3 (13) 34.0
 
Feb. 26, 2021, 7 a.m. 6.0 ppb (6) 1.0 ppb (1) N/A 5.0 ppb (5) N/A N/A 39.0 ppb (37) N/A N/A 3.0 μg/m3 (13) 37.0
 
Feb. 26, 2021, 6 a.m. 8.0 ppb (8) 1.0 ppb (1) N/A 7.0 ppb (7) N/A N/A 37.0 ppb (35) N/A N/A 3.0 μg/m3 (13) 35.0
 
Feb. 26, 2021, 5 a.m. 15.0 ppb (15) 2.0 ppb (2) N/A 13.0 ppb (13) N/A N/A 31.0 ppb (29) N/A N/A 5.0 μg/m3 (21) 29.0
 
Feb. 26, 2021, 4 a.m. 6.0 ppb (6) 1.0 ppb (1) N/A 5.0 ppb (5) N/A N/A 39.0 ppb (37) N/A N/A 3.0 μg/m3 (13) 37.0
 
Feb. 26, 2021, 3 a.m. 6.0 ppb (6) 1.0 ppb (1) N/A 5.0 ppb (5) N/A N/A 39.0 ppb (37) N/A N/A 3.0 μg/m3 (13) 37.0
 
Feb. 26, 2021, 2 a.m. 5.0 ppb (5) 1.0 ppb (1) N/A 4.0 ppb (4) N/A N/A 40.0 ppb (38) N/A N/A 3.0 μg/m3 (13) 38.0
 
Feb. 26, 2021, 1 a.m. 4.0 ppb (4) 2.0 ppb (2) N/A 3.0 ppb (3) N/A N/A 41.0 ppb (38) N/A N/A 3.0 μg/m3 (13) 38.0
 
Feb. 26, 2021, midnight 7.0 ppb (7) 2.0 ppb (2) N/A 5.0 ppb (5) N/A N/A 41.0 ppb (38) N/A N/A 3.0 μg/m3 (13) 38.0
 
Feb. 25, 2021, 11 p.m. 8.0 ppb (8) 3.0 ppb (3) N/A 5.0 ppb (5) N/A N/A 41.0 ppb (38) N/A N/A 3.0 μg/m3 (13) 38.0
 
Feb. 25, 2021, 10 p.m. 6.0 ppb (6) 2.0 ppb (2) N/A 4.0 ppb (4) N/A N/A 42.0 ppb (39) N/A N/A 3.0 μg/m3 (13) 39.0
 
Feb. 25, 2021, 9 p.m. 8.0 ppb (8) 3.0 ppb (3) N/A 5.0 ppb (5) N/A N/A 42.0 ppb (39) N/A N/A 2.0 μg/m3 (9) 39.0
 
Feb. 25, 2021, 8 p.m. 9.0 ppb (9) 4.0 ppb (4) N/A 5.0 ppb (5) N/A N/A 43.0 ppb (40) N/A N/A 2.0 μg/m3 (9) 40.0
 
Feb. 25, 2021, 7 p.m. 6.0 ppb (6) 3.0 ppb (3) N/A 3.0 ppb (3) N/A N/A 44.0 ppb (41) N/A N/A 1.0 μg/m3 (5) 41.0
 
Feb. 25, 2021, 6 p.m. 6.0 ppb (6) 3.0 ppb (3) N/A 3.0 ppb (3) N/A N/A 44.0 ppb (41) N/A N/A 1.0 μg/m3 (5) 41.0
 
Feb. 25, 2021, 5 p.m. 8.0 ppb (8) 3.0 ppb (3) N/A 5.0 ppb (5) N/A N/A 43.0 ppb (40) N/A N/A 1.0 μg/m3 (5) 40.0
 
Feb. 25, 2021, 4 p.m. 6.0 ppb (6) 3.0 ppb (3) N/A 4.0 ppb (4) N/A N/A 42.0 ppb (39) N/A N/A 1.0 μg/m3 (5) 39.0
 
Feb. 25, 2021, 3 p.m. 4.0 ppb (4) 2.0 ppb (2) N/A 2.0 ppb (2) N/A N/A 43.0 ppb (40) N/A N/A 1.0 μg/m3 (5) 40.0
 
Feb. 25, 2021, 2 p.m. 4.0 ppb (4) 2.0 ppb (2) N/A 2.0 ppb (2) N/A N/A 43.0 ppb (40) N/A N/A 1.0 μg/m3 (5) 40.0
 
Feb. 25, 2021, 1 p.m. 5.0 ppb (5) 2.0 ppb (2) N/A 3.0 ppb (3) N/A N/A 41.0 ppb (38) N/A N/A 1.0 μg/m3 (5) 38.0
 
Feb. 25, 2021, noon 5.0 ppb (5) 2.0 ppb (2) N/A 3.0 ppb (3) N/A N/A 37.0 ppb (35) N/A N/A 1.0 μg/m3 (5) 35.0
 
Feb. 25, 2021, 11 a.m. 8.0 ppb (8) 2.0 ppb (2) N/A 5.0 ppb (5) N/A N/A 34.0 ppb (32) N/A N/A 2.0 μg/m3 (9) 32.0
 
Feb. 25, 2021, 10 a.m. 5.0 ppb (5) 2.0 ppb (2) N/A 4.0 ppb (4) N/A N/A 39.0 ppb (37) N/A N/A 3.0 μg/m3 (13) 37.0
 
Feb. 25, 2021, 9 a.m. 4.0 ppb (4) 1.0 ppb (1) N/A 3.0 ppb (3) N/A N/A 43.0 ppb (40) N/A N/A 4.0 μg/m3 (17) 40.0
 
Feb. 25, 2021, 8 a.m. 5.0 ppb (5) 1.0 ppb (1) N/A 4.0 ppb (4) N/A N/A N/A N/A N/A 5.0 μg/m3 (21) 21.0
 
Feb. 25, 2021, 7 a.m. N/A N/A N/A N/A N/A N/A 44.0 ppb (41) N/A N/A 4.0 μg/m3 (17) 41.0
 
Feb. 25, 2021, 6 a.m. N/A N/A N/A N/A N/A N/A 42.0 ppb (39) N/A N/A 4.0 μg/m3 (17) 39.0
 
Feb. 25, 2021, 5 a.m. N/A N/A N/A N/A N/A N/A 38.0 ppb (36) N/A N/A 5.0 μg/m3 (21) 36.0
 
Feb. 25, 2021, 4 a.m. 12.0 ppb (12) 4.0 ppb (4) N/A 9.0 ppb (9) N/A N/A 43.0 ppb (40) N/A N/A 5.0 μg/m3 (21) 40.0
 
Feb. 25, 2021, 3 a.m. 15.0 ppb (15) 5.0 ppb (5) N/A 10.0 ppb (10) N/A N/A 43.0 ppb (40) N/A N/A 4.0 μg/m3 (17) 40.0
 
Feb. 25, 2021, 2 a.m. 12.0 ppb (12) 4.0 ppb (4) N/A 8.0 ppb (8) N/A N/A 42.0 ppb (39) N/A N/A 4.0 μg/m3 (17) 39.0
 
Feb. 25, 2021, 1 a.m. 17.0 ppb (17) 5.0 ppb (5) N/A 12.0 ppb (12) N/A N/A 40.0 ppb (38) N/A N/A 5.0 μg/m3 (21) 38.0
 
Feb. 25, 2021, midnight 25.0 ppb (24) 9.0 ppb (9) N/A 16.0 ppb (16) N/A N/A 37.0 ppb (35) N/A N/A 5.0 μg/m3 (21) 35.0
 
Feb. 24, 2021, 11 p.m. 30.0 ppb (29) 11.0 ppb (11) N/A 20.0 ppb (19) N/A N/A 30.0 ppb (28) N/A N/A 5.0 μg/m3 (21) 29.0
 
Feb. 24, 2021, 10 p.m. 45.0 ppb (43) 19.0 ppb (18) N/A 26.0 ppb (25) N/A N/A 26.0 ppb (25) N/A N/A 5.0 μg/m3 (21) 43.0
 
Feb. 24, 2021, 9 p.m. 36.0 ppb (34) 16.0 ppb (16) N/A 20.0 ppb (19) N/A N/A 33.0 ppb (31) N/A N/A 4.0 μg/m3 (17) 34.0
 
Feb. 24, 2021, 8 p.m. 36.0 ppb (34) 17.0 ppb (17) N/A 19.0 ppb (18) N/A N/A 34.0 ppb (32) N/A N/A 4.0 μg/m3 (17) 34.0
 
Feb. 24, 2021, 7 p.m. 37.0 ppb (35) 16.0 ppb (16) N/A 21.0 ppb (20) N/A N/A 32.0 ppb (30) N/A N/A 4.0 μg/m3 (17) 35.0
 
Feb. 24, 2021, 6 p.m. 31.0 ppb (30) 13.0 ppb (13) N/A 18.0 ppb (17) N/A N/A 34.0 ppb (32) N/A N/A 4.0 μg/m3 (17) 32.0
 
Feb. 24, 2021, 5 p.m. 27.0 ppb (26) 13.0 ppb (13) N/A 14.0 ppb (14) N/A N/A 36.0 ppb (34) N/A N/A 4.0 μg/m3 (17) 34.0
 
Feb. 24, 2021, 4 p.m. 35.0 ppb (34) 18.0 ppb (17) N/A 17.0 ppb (17) N/A N/A 32.0 ppb (30) N/A N/A 4.0 μg/m3 (17) 34.0
 
Feb. 24, 2021, 3 p.m. 11.0 ppb (11) 5.0 ppb (5) N/A 6.0 ppb (6) N/A N/A 39.0 ppb (37) N/A N/A 3.0 μg/m3 (13) 37.0
 
Feb. 24, 2021, 2 p.m. 19.0 ppb (18) 11.0 ppb (11) N/A 9.0 ppb (9) N/A N/A 35.0 ppb (33) N/A N/A 4.0 μg/m3 (17) 33.0
 
Feb. 24, 2021, 1 p.m. 19.0 ppb (18) 8.0 ppb (8) N/A 11.0 ppb (11) N/A N/A 30.0 ppb (28) N/A N/A 6.0 μg/m3 (25) 28.0
 
Feb. 24, 2021, noon 68.0 ppb (66) 37.0 ppb (35) N/A 32.0 ppb (31) N/A N/A 12.0 ppb (12) N/A N/A 8.0 μg/m3 (34) 66.0
 
Feb. 24, 2021, 11 a.m. 66.0 ppb (64) 32.0 ppb (31) N/A 34.0 ppb (33) N/A N/A 8.0 ppb (8) N/A N/A 5.0 μg/m3 (21) 64.0
 
Feb. 24, 2021, 10 a.m. 81.0 ppb (80) 44.0 ppb (42) N/A 36.0 ppb (34) N/A N/A 6.0 ppb (6) N/A N/A 4.0 μg/m3 (17) 80.0
 
Feb. 24, 2021, 9 a.m. 56.0 ppb (54) 24.0 ppb (23) N/A 32.0 ppb (31) N/A N/A 11.0 ppb (11) N/A N/A 4.0 μg/m3 (17) 54.0
 
Feb. 24, 2021, 8 a.m. 15.0 ppb (15) 3.0 ppb (3) N/A 12.0 ppb (12) N/A N/A 28.0 ppb (26) N/A N/A 4.0 μg/m3 (17) 26.0
 
Feb. 24, 2021, 7 a.m. 45.0 ppb (43) 15.0 ppb (15) N/A 29.0 ppb (28) N/A N/A 16.0 ppb (15) N/A N/A 4.0 μg/m3 (17) 43.0
 
Feb. 24, 2021, 6 a.m. 28.0 ppb (27) 7.0 ppb (7) N/A 20.0 ppb (19) N/A N/A 23.0 ppb (22) N/A N/A 5.0 μg/m3 (21) 27.0
 
Feb. 24, 2021, 5 a.m. 14.0 ppb (14) 3.0 ppb (3) N/A 11.0 ppb (11) N/A N/A 32.0 ppb (30) N/A N/A 5.0 μg/m3 (21) 30.0
 
Feb. 24, 2021, 4 a.m. 8.0 ppb (8) 1.0 ppb (1) N/A 7.0 ppb (7) N/A N/A 35.0 ppb (33) N/A N/A 6.0 μg/m3 (25) 33.0
 
Feb. 24, 2021, 3 a.m. 7.0 ppb (7) 1.0 ppb (1) N/A 6.0 ppb (6) N/A N/A 36.0 ppb (34) N/A N/A 8.0 μg/m3 (34) 34.0
 
Feb. 24, 2021, 2 a.m. 13.0 ppb (13) 2.0 ppb (2) N/A 11.0 ppb (11) N/A N/A 34.0 ppb (32) N/A N/A 9.0 μg/m3 (38) 38.0
 
Feb. 24, 2021, 1 a.m. 21.0 ppb (20) 4.0 ppb (4) N/A 18.0 ppb (17) N/A N/A 29.0 ppb (27) N/A N/A 10.0 μg/m3 (42) 42.0
 
Feb. 24, 2021, midnight 16.0 ppb (16) 3.0 ppb (3) N/A 13.0 ppb (13) N/A N/A 35.0 ppb (33) N/A N/A 10.0 μg/m3 (42) 42.0
 
Feb. 23, 2021, 11 p.m. 14.0 ppb (14) 3.0 ppb (3) N/A 12.0 ppb (12) N/A N/A 38.0 ppb (36) N/A N/A 9.0 μg/m3 (38) 38.0
 
Feb. 23, 2021, 10 p.m. 18.0 ppb (17) 4.0 ppb (4) N/A 14.0 ppb (14) N/A N/A 37.0 ppb (35) N/A N/A 8.0 μg/m3 (34) 35.0
 
Feb. 23, 2021, 9 p.m. 26.0 ppb (25) 9.0 ppb (9) N/A 17.0 ppb (17) N/A N/A 35.0 ppb (33) N/A N/A 8.0 μg/m3 (34) 34.0
 
Feb. 23, 2021, 8 p.m. 26.0 ppb (25) 9.0 ppb (9) N/A 17.0 ppb (17) N/A N/A 38.0 ppb (36) N/A N/A 8.0 μg/m3 (34) 36.0
 
Feb. 23, 2021, 7 p.m. 29.0 ppb (28) 11.0 ppb (11) N/A 18.0 ppb (17) N/A N/A 39.0 ppb (37) N/A N/A 8.0 μg/m3 (34) 37.0
 
Feb. 23, 2021, 6 p.m. 28.0 ppb (27) 11.0 ppb (11) N/A 17.0 ppb (17) N/A N/A 40.0 ppb (38) N/A N/A 8.0 μg/m3 (34) 38.0
 
Feb. 23, 2021, 5 p.m. 32.0 ppb (31) 15.0 ppb (15) N/A 16.0 ppb (16) N/A N/A 38.0 ppb (36) N/A N/A 9.0 μg/m3 (38) 38.0
 
Feb. 23, 2021, 4 p.m. 27.0 ppb (26) 13.0 ppb (13) N/A 14.0 ppb (14) N/A N/A 39.0 ppb (37) N/A N/A 9.0 μg/m3 (38) 38.0
 
Feb. 23, 2021, 3 p.m. 19.0 ppb (18) 8.0 ppb (8) N/A 11.0 ppb (11) N/A N/A 43.0 ppb (40) N/A N/A 8.0 μg/m3 (34) 40.0
 
Feb. 23, 2021, 2 p.m. 19.0 ppb (18) 7.0 ppb (7) N/A 12.0 ppb (12) N/A N/A 40.0 ppb (38) N/A N/A 9.0 μg/m3 (38) 38.0
 
Feb. 23, 2021, 1 p.m. 33.0 ppb (32) 11.0 ppb (11) N/A 21.0 ppb (20) N/A N/A 30.0 ppb (28) N/A N/A 9.0 μg/m3 (38) 38.0
 
Feb. 23, 2021, noon 45.0 ppb (43) 16.0 ppb (16) N/A 29.0 ppb (28) N/A N/A 22.0 ppb (21) N/A N/A 9.0 μg/m3 (38) 43.0
 
Feb. 23, 2021, 11 a.m. 42.0 ppb (40) 15.0 ppb (15) N/A 27.0 ppb (26) N/A N/A 21.0 ppb (20) N/A N/A 8.0 μg/m3 (34) 40.0
 
Feb. 23, 2021, 10 a.m. 39.0 ppb (37) 15.0 ppb (15) N/A 25.0 ppb (24) N/A N/A 21.0 ppb (20) N/A N/A 9.0 μg/m3 (38) 38.0
 
Feb. 23, 2021, 9 a.m. 42.0 ppb (40) 14.0 ppb (14) N/A 28.0 ppb (27) N/A N/A 16.0 ppb (15) N/A N/A 8.0 μg/m3 (34) 40.0
 
Feb. 23, 2021, 8 a.m. 46.0 ppb (44) 20.0 ppb (19) N/A 27.0 ppb (26) N/A N/A 17.0 ppb (16) N/A N/A 7.0 μg/m3 (30) 44.0
 
Feb. 23, 2021, 7 a.m. 20.0 ppb (19) 4.0 ppb (4) N/A 16.0 ppb (16) N/A N/A 23.0 ppb (22) N/A N/A 8.0 μg/m3 (34) 34.0
 
Feb. 23, 2021, 6 a.m. 8.0 ppb (8) 1.0 ppb (1) N/A 7.0 ppb (7) N/A N/A 32.0 ppb (30) N/A N/A 5.0 μg/m3 (21) 30.0
 
Feb. 23, 2021, 5 a.m. 6.0 ppb (6) 1.0 ppb (1) N/A 5.0 ppb (5) N/A N/A 34.0 ppb (32) N/A N/A 4.0 μg/m3 (17) 32.0
 
Feb. 23, 2021, 4 a.m. 8.0 ppb (8) 1.0 ppb (1) N/A 8.0 ppb (8) N/A N/A 28.0 ppb (26) N/A N/A 5.0 μg/m3 (21) 26.0
 
Feb. 23, 2021, 3 a.m. 31.0 ppb (30) 10.0 ppb (10) N/A 21.0 ppb (20) N/A N/A 16.0 ppb (15) N/A N/A 7.0 μg/m3 (30) 30.0
 
Feb. 23, 2021, 2 a.m. 16.0 ppb (16) 3.0 ppb (3) N/A 13.0 ppb (13) N/A N/A 26.0 ppb (25) N/A N/A 8.0 μg/m3 (34) 34.0
 
Feb. 23, 2021, 1 a.m. 20.0 ppb (19) 2.0 ppb (2) N/A 18.0 ppb (17) N/A N/A 20.0 ppb (19) N/A N/A 9.0 μg/m3 (38) 38.0
 
Feb. 23, 2021, midnight 29.0 ppb (28) 8.0 ppb (8) N/A 21.0 ppb (20) N/A N/A 16.0 ppb (15) N/A N/A 8.0 μg/m3 (34) 34.0
 
Feb. 22, 2021, 11 p.m. 34.0 ppb (33) 11.0 ppb (11) N/A 23.0 ppb (22) N/A N/A 23.0 ppb (22) N/A N/A 9.0 μg/m3 (38) 38.0
 
Feb. 22, 2021, 10 p.m. 27.0 ppb (26) 10.0 ppb (10) N/A 17.0 ppb (17) N/A N/A 29.0 ppb (27) N/A N/A 13.0 μg/m3 (53) 53.0
 
Feb. 22, 2021, 9 p.m. 32.0 ppb (31) 13.0 ppb (13) N/A 19.0 ppb (18) N/A N/A 30.0 ppb (28) N/A N/A 14.0 μg/m3 (55) 55.0
 
Feb. 22, 2021, 8 p.m. 39.0 ppb (37) 17.0 ppb (17) N/A 22.0 ppb (21) N/A N/A 30.0 ppb (28) N/A N/A 8.0 μg/m3 (34) 37.0
 
Feb. 22, 2021, 7 p.m. 38.0 ppb (36) 17.0 ppb (17) N/A 21.0 ppb (20) N/A N/A 30.0 ppb (28) N/A N/A 7.0 μg/m3 (30) 36.0
 
Feb. 22, 2021, 6 p.m. 41.0 ppb (39) 19.0 ppb (18) N/A 22.0 ppb (21) N/A N/A 31.0 ppb (29) N/A N/A 8.0 μg/m3 (34) 39.0
 
Feb. 22, 2021, 5 p.m. 40.0 ppb (38) 19.0 ppb (18) N/A 21.0 ppb (20) N/A N/A 32.0 ppb (30) N/A N/A 10.0 μg/m3 (42) 42.0
 
Feb. 22, 2021, 4 p.m. 40.0 ppb (38) 19.0 ppb (18) N/A 21.0 ppb (20) N/A N/A 32.0 ppb (30) N/A N/A 10.0 μg/m3 (42) 42.0
 
Feb. 22, 2021, 3 p.m. 55.0 ppb (53) 28.0 ppb (27) N/A 27.0 ppb (26) N/A N/A 22.0 ppb (21) N/A N/A 10.0 μg/m3 (42) 53.0
 
Feb. 22, 2021, 2 p.m. 66.0 ppb (64) 34.0 ppb (33) N/A 32.0 ppb (31) N/A N/A 15.0 ppb (14) N/A N/A 10.0 μg/m3 (42) 64.0
 
Feb. 22, 2021, 1 p.m. 83.0 ppb (82) 47.0 ppb (45) N/A 37.0 ppb (35) N/A N/A 8.0 ppb (8) N/A N/A 10.0 μg/m3 (42) 82.0
 
Feb. 22, 2021, noon 91.0 ppb (91) 51.0 ppb (49) N/A 40.0 ppb (38) N/A N/A 4.0 ppb (4) N/A N/A 11.0 μg/m3 (46) 91.0
 
Feb. 22, 2021, 11 a.m. 77.0 ppb (76) 40.0 ppb (38) N/A 38.0 ppb (36) N/A N/A 4.0 ppb (4) N/A N/A 11.0 μg/m3 (46) 76.0
 
Feb. 22, 2021, 10 a.m. 78.0 ppb (77) 41.0 ppb (39) N/A 37.0 ppb (35) N/A N/A 4.0 ppb (4) N/A N/A 12.0 μg/m3 (50) 77.0
 
Feb. 22, 2021, 9 a.m. 89.0 ppb (89) 49.0 ppb (47) N/A 40.0 ppb (38) N/A N/A 3.0 ppb (3) N/A N/A 10.0 μg/m3 (42) 89.0
 
Feb. 22, 2021, 8 a.m. 94.0 ppb (94) 54.0 ppb (51) N/A 40.0 ppb (38) N/A N/A N/A N/A N/A 9.0 μg/m3 (38) 94.0
 
Feb. 22, 2021, 7 a.m. N/A N/A N/A N/A N/A N/A 2.0 ppb (2) N/A N/A 9.0 μg/m3 (38) 38.0
 
Feb. 22, 2021, 6 a.m. N/A N/A N/A N/A N/A N/A 2.0 ppb (2) N/A N/A 10.0 μg/m3 (42) 42.0
 
Feb. 22, 2021, 5 a.m. N/A N/A N/A N/A N/A N/A 2.0 ppb (2) N/A N/A 9.0 μg/m3 (38) 38.0
 
Feb. 22, 2021, 4 a.m. 90.0 ppb (90) 50.0 ppb (48) N/A 40.0 ppb (38) N/A N/A 3.0 ppb (3) N/A N/A 9.0 μg/m3 (38) 90.0
 
Feb. 22, 2021, 3 a.m. 87.0 ppb (87) 45.0 ppb (43) N/A 42.0 ppb (40) N/A N/A 3.0 ppb (3) N/A N/A 9.0 μg/m3 (38) 87.0
 
Feb. 22, 2021, 2 a.m. 77.0 ppb (76) 36.0 ppb (34) N/A 42.0 ppb (40) N/A N/A 4.0 ppb (4) N/A N/A 8.0 μg/m3 (34) 76.0
 
Feb. 22, 2021, 1 a.m. 48.0 ppb (46) 16.0 ppb (16) N/A 32.0 ppb (31) N/A N/A 12.0 ppb (12) N/A N/A 7.0 μg/m3 (30) 46.0
 
Feb. 22, 2021, midnight 15.0 ppb (15) 1.0 ppb (1) N/A 14.0 ppb (14) N/A N/A 31.0 ppb (29) N/A N/A 5.0 μg/m3 (21) 29.0
 
Feb. 21, 2021, 11 p.m. 13.0 ppb (13) 1.0 ppb (1) N/A 12.0 ppb (12) N/A N/A 33.0 ppb (31) N/A N/A 4.0 μg/m3 (17) 31.0
 
Feb. 21, 2021, 10 p.m. 6.0 ppb (6) 1.0 ppb (1) N/A 5.0 ppb (5) N/A N/A 40.0 ppb (38) N/A N/A 3.0 μg/m3 (13) 38.0
 
Feb. 21, 2021, 9 p.m. 3.0 ppb (3) 1.0 ppb (1) N/A 2.0 ppb (2) N/A N/A 43.0 ppb (40) N/A N/A 3.0 μg/m3 (13) 40.0
 
Feb. 21, 2021, 8 p.m. 3.0 ppb (3) 1.0 ppb (1) N/A 2.0 ppb (2) N/A N/A 44.0 ppb (41) N/A N/A 3.0 μg/m3 (13) 41.0
 
Feb. 21, 2021, 7 p.m. 2.0 ppb (2) 1.0 ppb (1) N/A 1.0 ppb (1) N/A N/A 44.0 ppb (41) N/A N/A 3.0 μg/m3 (13) 41.0
 
Feb. 21, 2021, 6 p.m. 3.0 ppb (3) 1.0 ppb (1) N/A 2.0 ppb (2) N/A N/A 44.0 ppb (41) N/A N/A 3.0 μg/m3 (13) 41.0
 
Feb. 21, 2021, 5 p.m. 2.0 ppb (2) 1.0 ppb (1) N/A 1.0 ppb (1) N/A N/A 44.0 ppb (41) N/A N/A 3.0 μg/m3 (13) 41.0
 
Feb. 21, 2021, 4 p.m. 2.0 ppb (2) 1.0 ppb (1) N/A 1.0 ppb (1) N/A N/A 43.0 ppb (40) N/A N/A 3.0 μg/m3 (13) 40.0
 
Feb. 21, 2021, 3 p.m. 2.0 ppb (2) 1.0 ppb (1) N/A 1.0 ppb (1) N/A N/A 42.0 ppb (39) N/A N/A 3.0 μg/m3 (13) 39.0
 
Feb. 21, 2021, 2 p.m. 3.0 ppb (3) 1.0 ppb (1) N/A 2.0 ppb (2) N/A N/A 41.0 ppb (38) N/A N/A 4.0 μg/m3 (17) 38.0
 
Feb. 21, 2021, 1 p.m. 6.0 ppb (6) 2.0 ppb (2) N/A 5.0 ppb (5) N/A N/A 37.0 ppb (35) N/A N/A 4.0 μg/m3 (17) 35.0
 
Feb. 21, 2021, noon 11.0 ppb (11) 2.0 ppb (2) N/A 9.0 ppb (9) N/A N/A 32.0 ppb (30) N/A N/A 4.0 μg/m3 (17) 30.0
 
Feb. 21, 2021, 11 a.m. 10.0 ppb (10) 1.0 ppb (1) N/A 9.0 ppb (9) N/A N/A 31.0 ppb (29) N/A N/A 4.0 μg/m3 (17) 29.0
 
Feb. 21, 2021, 10 a.m. 8.0 ppb (8) 1.0 ppb (1) N/A 8.0 ppb (8) N/A N/A 34.0 ppb (32) N/A N/A 4.0 μg/m3 (17) 32.0
 
Feb. 21, 2021, 9 a.m. 9.0 ppb (9) 1.0 ppb (1) N/A 8.0 ppb (8) N/A N/A 34.0 ppb (32) N/A N/A 4.0 μg/m3 (17) 32.0
 
Feb. 21, 2021, 8 a.m. 8.0 ppb (8) 1.0 ppb (1) N/A 7.0 ppb (7) N/A N/A 36.0 ppb (34) N/A N/A 4.0 μg/m3 (17) 34.0
 
Feb. 21, 2021, 7 a.m. 5.0 ppb (5) 0.0 ppb (0) N/A 5.0 ppb (5) N/A N/A 38.0 ppb (36) N/A N/A 4.0 μg/m3 (17) 36.0
 
Feb. 21, 2021, 6 a.m. 5.0 ppb (5) 1.0 ppb (1) N/A 4.0 ppb (4) N/A N/A 39.0 ppb (37) N/A N/A 4.0 μg/m3 (17) 37.0
 
Feb. 21, 2021, 5 a.m. 6.0 ppb (6) 1.0 ppb (1) N/A 5.0 ppb (5) N/A N/A 39.0 ppb (37) N/A N/A 4.0 μg/m3 (17) 37.0
 
Feb. 21, 2021, 4 a.m. 4.0 ppb (4) 1.0 ppb (1) N/A 3.0 ppb (3) N/A N/A 41.0 ppb (38) N/A N/A 4.0 μg/m3 (17) 38.0
 
Feb. 21, 2021, 3 a.m. 3.0 ppb (3) 0.0 ppb (0) N/A 2.0 ppb (2) N/A N/A 42.0 ppb (39) N/A N/A 3.0 μg/m3 (13) 39.0
 
Feb. 21, 2021, 2 a.m. 3.0 ppb (3) 1.0 ppb (1) N/A 2.0 ppb (2) N/A N/A 42.0 ppb (39) N/A N/A 3.0 μg/m3 (13) 39.0
 
Feb. 21, 2021, 1 a.m. 4.0 ppb (4) 1.0 ppb (1) N/A 3.0 ppb (3) N/A N/A 41.0 ppb (38) N/A N/A 4.0 μg/m3 (17) 38.0
 
Feb. 21, 2021, midnight 4.0 ppb (4) 0.0 ppb (0) N/A 4.0 ppb (4) N/A N/A 40.0 ppb (38) N/A N/A 4.0 μg/m3 (17) 38.0
 
Feb. 20, 2021, 11 p.m. 5.0 ppb (5) 1.0 ppb (1) N/A 4.0 ppb (4) N/A N/A 40.0 ppb (38) N/A N/A 5.0 μg/m3 (21) 38.0
 
Feb. 20, 2021, 10 p.m. 3.0 ppb (3) 1.0 ppb (1) N/A 2.0 ppb (2) N/A N/A 44.0 ppb (41) N/A N/A 5.0 μg/m3 (21) 41.0
 
Feb. 20, 2021, 9 p.m. 3.0 ppb (3) 1.0 ppb (1) N/A 2.0 ppb (2) N/A N/A 45.0 ppb (42) N/A N/A 4.0 μg/m3 (17) 42.0
 
Feb. 20, 2021, 8 p.m. 3.0 ppb (3) 1.0 ppb (1) N/A 2.0 ppb (2) N/A N/A 45.0 ppb (42) N/A N/A 4.0 μg/m3 (17) 42.0
 
Feb. 20, 2021, 7 p.m. 4.0 ppb (4) 1.0 ppb (1) N/A 3.0 ppb (3) N/A N/A 45.0 ppb (42) N/A N/A 5.0 μg/m3 (21) 42.0
 
Feb. 20, 2021, 6 p.m. 5.0 ppb (5) 2.0 ppb (2) N/A 3.0 ppb (3) N/A N/A 43.0 ppb (40) N/A N/A 5.0 μg/m3 (21) 40.0
 
Feb. 20, 2021, 5 p.m. 4.0 ppb (4) 2.0 ppb (2) N/A 3.0 ppb (3) N/A N/A 42.0 ppb (39) N/A N/A 4.0 μg/m3 (17) 39.0
 
Feb. 20, 2021, 4 p.m. 4.0 ppb (4) 2.0 ppb (2) N/A 3.0 ppb (3) N/A N/A 40.0 ppb (38) N/A N/A 5.0 μg/m3 (21) 38.0
 
Feb. 20, 2021, 3 p.m. 6.0 ppb (6) 2.0 ppb (2) N/A 4.0 ppb (4) N/A N/A 37.0 ppb (35) N/A N/A 5.0 μg/m3 (21) 35.0
 
Feb. 20, 2021, 2 p.m. 8.0 ppb (8) 2.0 ppb (2) N/A 6.0 ppb (6) N/A N/A 33.0 ppb (31) N/A N/A 6.0 μg/m3 (25) 31.0
 
Feb. 20, 2021, 1 p.m. 16.0 ppb (16) 4.0 ppb (4) N/A 12.0 ppb (12) N/A N/A 26.0 ppb (25) N/A N/A 7.0 μg/m3 (30) 30.0
 
Feb. 20, 2021, noon 47.0 ppb (45) 19.0 ppb (18) N/A 28.0 ppb (27) N/A N/A 11.0 ppb (11) N/A N/A 9.0 μg/m3 (38) 45.0
 
Feb. 20, 2021, 11 a.m. 43.0 ppb (41) 15.0 ppb (15) N/A 28.0 ppb (27) N/A N/A 11.0 ppb (11) N/A N/A 9.0 μg/m3 (38) 41.0
 
Feb. 20, 2021, 10 a.m. 34.0 ppb (33) 8.0 ppb (8) N/A 26.0 ppb (25) N/A N/A 14.0 ppb (13) N/A N/A 9.0 μg/m3 (38) 38.0
 
Feb. 20, 2021, 9 a.m. 16.0 ppb (16) 4.0 ppb (4) N/A 12.0 ppb (12) N/A N/A 27.0 ppb (25) N/A N/A 6.0 μg/m3 (25) 25.0
 
Feb. 20, 2021, 8 a.m. 7.0 ppb (7) 0.0 ppb (0) N/A 6.0 ppb (6) N/A N/A 33.0 ppb (31) N/A N/A 5.0 μg/m3 (21) 31.0
 
Feb. 20, 2021, 7 a.m. 6.0 ppb (6) 1.0 ppb (1) N/A 5.0 ppb (5) N/A N/A 34.0 ppb (32) N/A N/A 6.0 μg/m3 (25) 32.0
 
Feb. 20, 2021, 6 a.m. 5.0 ppb (5) 0.0 ppb (0) N/A 5.0 ppb (5) N/A N/A 35.0 ppb (33) N/A N/A 5.0 μg/m3 (21) 33.0
 
Feb. 20, 2021, 5 a.m. 5.0 ppb (5) 1.0 ppb (1) N/A 5.0 ppb (5) N/A N/A 36.0 ppb (34) N/A N/A 5.0 μg/m3 (21) 34.0
 
Feb. 20, 2021, 4 a.m. 6.0 ppb (6) 1.0 ppb (1) N/A 5.0 ppb (5) N/A N/A 36.0 ppb (34) N/A N/A 5.0 μg/m3 (21) 34.0
 
Feb. 20, 2021, 3 a.m. 6.0 ppb (6) 1.0 ppb (1) N/A 6.0 ppb (6) N/A N/A 35.0 ppb (33) N/A N/A 5.0 μg/m3 (21) 33.0
 
Feb. 20, 2021, 2 a.m. 6.0 ppb (6) 0.0 ppb (0) N/A 6.0 ppb (6) N/A N/A 36.0 ppb (34) N/A N/A 5.0 μg/m3 (21) 34.0
 
Feb. 20, 2021, 1 a.m. 7.0 ppb (7) 1.0 ppb (1) N/A 6.0 ppb (6) N/A N/A 35.0 ppb (33) N/A N/A 6.0 μg/m3 (25) 33.0
 
Feb. 20, 2021, midnight 7.0 ppb (7) 1.0 ppb (1) N/A 7.0 ppb (7) N/A N/A 35.0 ppb (33) N/A N/A 6.0 μg/m3 (25) 33.0
 
Feb. 19, 2021, 11 p.m. 7.0 ppb (7) 0.0 ppb (0) N/A 7.0 ppb (7) N/A N/A 36.0 ppb (34) N/A N/A 6.0 μg/m3 (25) 34.0
 
Feb. 19, 2021, 10 p.m. 7.0 ppb (7) 0.0 ppb (0) N/A 7.0 ppb (7) N/A N/A 36.0 ppb (34) N/A N/A 5.0 μg/m3 (21) 34.0
 
Feb. 19, 2021, 9 p.m. 7.0 ppb (7) 1.0 ppb (1) N/A 6.0 ppb (6) N/A N/A 37.0 ppb (35) N/A N/A 5.0 μg/m3 (21) 35.0
 
Feb. 19, 2021, 8 p.m. 7.0 ppb (7) 1.0 ppb (1) N/A 6.0 ppb (6) N/A N/A 38.0 ppb (36) N/A N/A 5.0 μg/m3 (21) 36.0
 
Feb. 19, 2021, 7 p.m. 7.0 ppb (7) 1.0 ppb (1) N/A 6.0 ppb (6) N/A N/A 38.0 ppb (36) N/A N/A 6.0 μg/m3 (25) 36.0
 
Feb. 19, 2021, 6 p.m. 8.0 ppb (8) 2.0 ppb (2) N/A 6.0 ppb (6) N/A N/A 37.0 ppb (35) N/A N/A 6.0 μg/m3 (25) 35.0
 
Feb. 19, 2021, 5 p.m. 8.0 ppb (8) 2.0 ppb (2) N/A 6.0 ppb (6) N/A N/A 37.0 ppb (35) N/A N/A 6.0 μg/m3 (25) 35.0
 
Feb. 19, 2021, 4 p.m. 7.0 ppb (7) 1.0 ppb (1) N/A 6.0 ppb (6) N/A N/A 36.0 ppb (34) N/A N/A 6.0 μg/m3 (25) 34.0
 
Feb. 19, 2021, 3 p.m. 7.0 ppb (7) 1.0 ppb (1) N/A 5.0 ppb (5) N/A N/A 37.0 ppb (35) N/A N/A 5.0 μg/m3 (21) 35.0