Summary of Ambient Air Monitoring (Winter)
from 1993 to 2000
|
Parameters
|
Hong Kong Air Quality Objective
|
Baseline
|
Monitoring Results
|
||||||
|---|---|---|---|---|---|---|---|---|---|
| 1993 |
1994
|
1995
|
1996
|
1997
|
1998
|
1999
|
2000
|
||
|
24 hr. Average
|
Jan |
Jan
|
Mar- Apr
|
Jan
|
Jan
|
Dec 97 - Jan 98
|
Feb
|
Mar- Apr
|
|
| Sulphur Dioxide (SO2) ug/m3 |
350
|
8 - 19
|
27 - 88
|
N/A
|
2.6 - 7.9
|
2.6 - 18.3
|
2.6 - 10.5
|
2.6
|
2.6 - 3
|
| Nitrogen Dioxide (NO2) ug/m3 |
150
|
38 - 90
|
88 - 121
|
71 - 160
|
39.5 - 64
|
24.5 - 94.1
|
26.3 - 94.1
|
16.9 - 43.3
|
8 - 19
|
| Total Suspended Particulates (TSP) ug/m3 |
260
|
43 - 109
|
111 - 219
|
75 - 161
|
74 - 189
|
73 - 188
|
56 - 186
|
94 - 169*
|
60 - 109
|
| Respirable Suspended Particulates (RSP) ug/m3 |
180
|
27 - 69
|
63 - 147
|
41 - 107
|
46 - 92
|
50 - 135
|
36 - 135
|
41 - 137*
|
44 - 79
|
| Nitrogen Oxides (NOx) ppb |
---
|
27 - 107
|
57 - 174
|
51 - 230
|
47 - 88
|
25 - 94
|
38 - 113
|
26 - 64
|
16 - 49#
|
| Non-methane Hydrocarbons (NMHC) ppm |
---
|
0.1 - 1.1
|
<0.1
|
N/A
|
<0.02
|
0.11 - 0.3
|
0.15 - 0.24
|
0.15 - 0.22
|
0.45 - 2.25#
|
| PCBs (total) ng/m3 |
---
|
Nil
|
0.0326
|
Nil
|
Nil
|
Nil
|
Nil
|
Nil
|
Nil
|
| Dioxins (total) pg/m3 |
---
|
0.131
|
0.020
|
0.011
|
0.053
|
0.144
|
0.063
|
0.022
|
0.038
|
| VOCs (total) ug/m3 |
---
|
88.3
|
91.72
|
81.08
|
86.47
|
71.37
|
41.8
|
14.4
|
46.4
|
| Prevailing Wind Direction |
---
|
North- east
|
East
|
East
|
North- east
|
North
|
North- east
|
North- east
|
North- east
|
Remarks :
- N/A : invalid data due to failure of monitoring instrument.
- Meteorological data were obtained on the roof of Technical building at CWTC.
- The Total 2,3,7,8-TCDD Toxicity Equivalence is the product sum of the concentration of all seventeen 2,3,7,8-substituted PCDDs/PCDFs congeners and their respective Toxicity Equivalence Factor (TEF). For those congeners with concentration found below the MDL, half MDL is used for calculation.
-* Active construction site situated near the sampling point. Construction site could be a source of suspended particulates and therefore it would contribute to the high TSP and RSP levels.
-# Starting from August 1999, results of NOx and NMHC are expressed in ug/m3 and mg/m3 respectively
