| 5.4.1.6 |
Air
pollutants in Hong Kong can be classified
as either Criteria Air Pollutants (CAPs)
or Toxic Air Pollutants (TAPs). CAPs are
those pollutants for which Air Quality Objectives
(AQOs) have been established. Table 5.4a
details the pollutants, their AQOs (EPD
1998d) based on averaging times, and the
number of monitoring stations at which non-compliances
with the AQO were recorded in 1998.
| Table
5.4a
Air Quality Objectives and Non-Compliance
Rate in 1998 (At 10 Monitoring Stations) |
Table
5.4a
Air Quality Objectives and Non-Compliance
Rate in 1998 (At 10 Monitoring Stations)
| Pollutant |
AQO
(ug m-3) |
AQO
Averaging Time |
Stations
Recording Non-Compliances (n=10)(1) |
| Sulphur
dioxide (SO2) |
80 |
1
year |
0 |
|
350 |
24
hour |
0 |
|
800 |
1
hour |
0 |
| Total
suspended particulates (TSP) |
80 |
1
year |
3 |
|
260 |
24
hour |
0 |
| Respirable
suspended particulates (RSP) |
55 |
1
year |
3 |
|
180 |
24
hour |
1 |
| Nitrogen
dioxide (NO2) |
80 |
1
year |
2 |
|
150 |
24
hour |
2 |
|
300 |
1
hour |
0 |
| Carbon
monoxide (CO) |
10,000 |
8
hour |
0 |
|
30,000 |
1
hour |
0 |
| Ozone
(O3) |
240 |
1
hour |
0 |
| Lead
(Pb) |
1.5 |
3
month |
0 |
Note:
(1) Monitoring results are from 9 monitoring
stations except for 24-hour NO2 which was
measured at 12 stations in 1998, although
insufficient data were collected at the
Kwun Tong, Central and Tap Mun stations
for assessment of their AQO compliance status.
Source: EPD (1998d)
|
| 5.4.1.7 |
The
information shows that the 1-year AQO for
respirable particulate matter (RSP) was
exceeded on more than one occasion at 3
out of the 9 monitoring sites (Yuen Long,
Mong Kok and Causeway Bay) and the 1-year
AQO for total suspended particulates (TSP)
was also exceeded in three locations - Yuen
Long, Sham Shui Po and Mong Kok.
|
| 5.4.1.8 |
There
were two locations (Mong Kok and Causeway
Bay) where non-compliances with the 1-year
AQO for NO2 in 1998 were recorded, and non-compliances
with the 24 hour AQO were recorded at Causeway
Bay and Central. On the basis of these data,
longer term exceedences of particulates
and nitrogen dioxide appear to be of greater
concern than short term (ie hourly or daily)
pollution events.
|
|