Con'td

WEEK 2

Noise Monitoring

Date: 30/11/2016

Time: 16:01:34

MEASUREMENT
DATE: 30th NOVEMBER 2016		TIME: 4.01 PM
MEASUREMENT TIME INTERVAL: 1 HOUR
EQUIPMENT
SOUND LEVEL METER MODEL: EXTECH INSTRUMENT SERIAL NO: 150105006
WEATHER CONDITION
WEATHER EQUIPMENT SERIAL NO: SM 15413297 PRESSURE (Pa): 1016 hPa		PRECIPITATION: RAINING/DRIZZLE
CLOUD COVER: CLEAR/SCATTERED CLOUD/PARTLY CLOUD/MOSTLY CLOUD/OVERCAST
AVERAGE WIND SPEED: 4 kph TEMPERATURE: 30˚C		HUMIDITY (%): 47%
DESCRIPTION AND OPERATING CONDITION OF THE SOUND SOURCE
LOCATION OF SITE: ALOR GAJAH ROUNDABOUT
DESCRIPTION OF SITE: THE ROUNDABOUT IS LOCATED BESIDES MAIN ROAD AND ALSO LOCATED OPPOSITES TO SHOP LOTS AND ALSO INDUSTRY AREA.
BUILDING GEOMETRY: SINGLE STOREY
GROUND COVER & CONDITION: TAR ROAD
PARAMETERS
HEIGHT OF MICROPHONE (Hr): 1.2 m		HEIGHT OF SOURCE (Hs): 1.46 m
DISTANCE BETWEEN SOURCE AND MICROPHONE (r): 3.54 m
ROAD TRAFFIC
# OF HEAVY VEHICLES (>3500KG) (Min 30): 65	# OF LIGHT VEHICLES (Min 30): 1389		AVERAGE SPEED: 60 km/h

We started off a bit late for the second week, we arrived at the location setting up the instrument as we've been doing before in the first week. We started at 16:58:01 in the evening and finished at 17:58:00 on the same occasion. So below are the results that we obtained after 1 hour of noise assessment for the second week. 

Discussion
Overview

Above are the value of noise level that are taken during 1 hour period of time:

Firstly, L10 is the noise level exceeded for 10% of the time of the measurement duration. This is often used to give an indication of the upper limit of fluctuating noise, such as that from road traffic. So for the 2^nd week, the value of L10 is 74 dB. Compared to the first week, it increased by 1.1 dB. Then for L50, it is the noise level exceeded for 50% of the measurement duration. Therefore the value of L50 is 67.4 dB. It is slightly increased. Next, the L90 is the noise level that is taken to be the ambient or background noise in the road traffic. The value of L90 is 62.5 dB. Compared to the first week, it is decreased by only 0.1 dB. Futhermore, the value of Max dB for this particular week 99.3 dB. This is due to heavy vehicles were passing by on the road traffic. In addition, Leq is the Sound Pressure Level in dB, time-averaged level and is equivalent to the total Sound Energy over a 1 hour period of time on the road traffic. The value of Leq is 73 dB for the second week.