Annex
1 Determination
of Sound Power Levels of the Fixed Noise Sources
1. The Sound Level Meter (SLM) was placed at a height of 1.2m above ground surface. The SLM was positioned at a place with no sound reflecting objects in its vicinity. The dominant noise emission is from the operation activities being assessed.
2. The SLM was positioned at a distance of 2 m away from the noise sources.
3. The SLM was calibrated immediately prior to and following each noise measurement.
4. The noise equivalent levels (Leq) with 2 minutes measurement period were recorded and converted to the sound power level using the following equation:
Lw = Leq
+ 20log r + 8
where:
Lw is
the sound power level of the source, dB(A)
Leq is
the equivalent sound pressure level, dB referenced to 2 x 10-5Pa
r is the slant
distance between noise source and the receiver (m)
5. The measured noise level and the estimated sound power level of the fixed noise sources arising from the operational activities are tabulated below.
|
Operational
Activities |
Location |
Measured Noise Levels, Leq, dB(A) |
Distance from source r, m |
Estimated Sound Power Level, dB(A) |
|
Material Hoist |
Sorting area, G/F |
73 |
2 |
87 |
|
Icing Machine |
WFM hall, G/F |
82 |
2 |
96 |
|
Lorries parking |
Car park, G/F |
70 |
2 |
84 |
|
Sampans Idling |
Berthing area |
88 |
2 |
102 |
|
Fish vessels Idling |
Berthing area |
88 |
2 |
102 |
|
Unloading of fish
containers from sea vessels |
Sorting area, G/F |
79 |
2 |
93 |
|
Auction and Marshalling |
WFM hall, G/F |
80 |
2 |
94 |
|
Weighting Operation |
WFM hall, G/F |
85 |
2 |
99 |
|
Loading of fish containers
to lorries |
Car park, G/F |
70 |
2 |
84 |