12
5
10
15
20
25
30
35
40
1
3
5
7
9
11
13
15
17
19
21
23
Time of Day
Avg Hourly NO
y
Concentration (ppb)
Sunday
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
May-Sep ‘95-‘98 Plaza Average Hourly NO
y
From Perry and Owens, AWMA, 2001