TABLE 1
Summary of  United States Ambient Air Quality Standard, Environment Canada’s
Maximum Acceptable levels, the Province of  Ontario’s Ambient Air Quality Criteria,
and Canada-Wide Standards
 Pollutant
Time
US EPA-National
Environment
Province  of
Canadian
Canada-wide
Unit
Ambient Air
Canada
Ontario
Council  of
Standards
Quality Standards
(Maximum
Ambient
Ministers of  the
P-Primary
Acceptable
Air Quality
Environment
S-Secondary
Level)
Criteria
Guidelines
3
3
Ozone
1-hour
235 µg/m
0.082 ppm
0.08 ppm
100-300 µg/m
0.12 ppm (P&S)
82 ppb
80 ppb
120 ppb
3
8-hour
157 µg/m
0.065 ppm
0.065 ppm
0.065 ppm
0.08 ppm (P&S)
65 ppb*
65 ppb*
65 ppb*
80 ppb*
(adopting the
(to be achieved
CWS)
by 2010)
3
24-hour
0.025 ppm
30-50 µg/m
25 ppb
3
Annual
0.015 ppm
30 µg/m
15 ppb
3
Sulphur
1-hour
n/a
0.334 ppm
0.250 ppm
450 µg/m
Dioxide
334 ppb
250 ppb
3
3-hour
1300 µg/m
0.50 ppm (S)
500 ppb
3
3
24-hour
365 µg/m
0.115 ppm
0.10 ppm
150-800 µg/m
0.14 ppm(P)
115 ppb
100 ppb
140 ppb
3
3
Annual
80 µg/m
0.023 ppm
0.02 ppm
30-60 µg/m
0.030 ppm
23 ppb
20 ppb
30 ppb
3
Nitrogen
1-hour
0.213 ppm
0.2 ppm
400-1000 µg/m
Dioxide
213 ppb
200 ppb
3
24-hour
0.106 ppm
0.10 ppm
200-300 µg/m
106 ppb
100 ppb
3
3
0.053 ppm
60-100 µg/m
Annual
100 µg/m
0.053 ppm (P&S)
53 ppb
53 ppb
3
3
Carbon
1-hour
40,000 µg/m
31 ppm
30 ppm
6000 µg/m
3
Monoxide
40 mg/m
31,000 ppb
30,000 ppb
35 ppm(P)
35,000 ppb
3
8-hour
10,000 µg/m
13 ppm
13 ppm
15,000-
3
3
10 mg/m
13,000 ppb
13,000 ppb
35,000 µg/m
3
9 ppm (P)
15-35 µg/m
9,000 ppb
3
3
3
24-hour
150 µg/m  (P&S)
50 µg/m
25 µg/m
PM
10
3
Annual
50 µg/m  (P&S)
3
3
3
24-hour
65 µg/m *
30 µg/m *
30 µg/m * (to be
PM
2.5
(adopting the CWS)
achieved by 2010)
3
Annual
15 µg/m *
3
Lead
Quarterly
1.5 µg/m
Average
*  Indicates statistical calculation necessary to determine compliance with standard
6