3.            NOISE


3.1         Monitoring Requirement


In accordance with the approved EM&A Manuals, Leq (30min) monitoring is conducted for at least once a week during the construction phase between 0700 and 1900 on normal weekdays at the designated monitoring locations.


3.2         Monitoring Equipment


The sound level meter used in noise monitoring will comply with the International Electrotechnical Commission Publication (IEC) 651:1979 (Type 1) and 804:1985 (Type 1) specifications as referred to in the Technical Memorandum issued under the Noise Control Ordinance (NCO).


Sound level calibrator will be used for the on-site calibration of the meter. This calibrator complies with the IEC Publication 942 (1988) Class 1 and ANSI S1.40 - 1984. Noise measurements were only accepted to be valid if the calibration levels from before and after the measurement agree to within 1.0dB.


Measurements shall be recorded to the nearest 0.1dB. This noise monitors are programmed to measure A-weighted equivalent continuous sound pressure level at 30-minute intervals between 0700 and 1900 on normal weekdays at least once a week when construction activities are underway.


Table 3.1 summarizes the noise monitoring equipment model being used for this project.


Table 3.1        Noise Monitoring Equipment





Serial Number



CEL-63X Series

Integrating Sound Level Meter




CL63X Series

Integrating Sound Level Meter




CL63X Series

Integrating Sound Level Meter















Wind Speed Anemometer




Wind Speed Anemometer



3.3         Monitoring Parameters and Frequency


Table 3.2 presents the noise monitoring parameters and frequencies.


Table 3.2        Monitoring Parameters and Frequencies of Noise Monitoring


Frequency and Period

LAeq (30min)


L10 and L90 will be recorded for reference

At each station at 0700-1900 hours on normal weekdays at a frequency of once a week




3.4         Monitoring Methodology


The monitoring procedures are as follows:


n   The monitoring station is set at a point 1m from the exterior of the sensitive receivers building façade and set at a position 1.2m above the ground. 

n   The battery condition is checked to ensure good functioning of the meter.

n   Parameters such as frequency weighting, the time weighting and the measurement time are set as follows:


n   frequency weighting : A

n   time weighting : Fast

n   measurement time : Weekly 30 minutes between 0700-1900 on normal weekdays


n   Prior to and after noise measurement, the meter shall be calibrated using the calibrator for 94.0 dB at 1000 Hz. If the difference in the calibration level before and after measurement is more than 1.0 dB, the measurement will be considered invalid and repeat of noise measurement is required after re-calibration or repair of the equipment.

n   Noise monitoring should be cancelled in the presence of fog, rain, and wind with a steady speed exceeding 5 m/s, or wind with gusts exceeding 10 m/s.

n   Noise measurement should be paused during periods of high intrusive noise if possible and observation shall be recorded when intrusive noise is not avoided.

n   At the end of the monitoring period, the Leq, L10 and L90 are recorded. In addition, site conditions and noise sources are recorded on a standard record sheet.


3.5         Maintenance / Calibration


            Maintenance and Calibration procedures are as follows:


n   The microphone head of the sound level meter and calibrator should be cleaned with a soft cloth at quarterly intervals.

n   The sound level meter and calibrator should be calibrated annually by a HOKLAS laboratory.

n   Relevant calibration certificates are provided in Appendix D.


3.6         Monitoring Locations


3.6.1     According to the EM&A Manual, three noise monitoring locations, namely KTD1, KTD2 and KER1, are covered by this Contract within the South Apron Area of Former Kai Tak Airport. The other two noise quality monitoring locations, which are identified in Cha Kwo Ling area, are farther than 300m away from the site boundary and thus not covered by this Contract. The monitoring works in Cha Kwo Ling area are covered by other Contract(s) respectively.


3.6.2     According to the approved alternative baseline air quality and noise monitoring locations (EPD reference: EP2/K19/A/21 Pt.5), the original monitoring locations (KTD1, KTD2 and KER1) are proposed to be replaced by alternative monitoring locations (KTD1a, KTD2a and KER1b) for noise monitoring, they are summarized in Table 3.3 and shown in Figure 2.


Table 3.3         Location of Noise Monitoring Station

Monitoring Station



Centre of Excellence in Paediatrics (Children’s Hospital)


G/IC Zone next to Kwun Tong Bypass (Future Hospital at Site 3C1)


Site Boundary at Cheung Yip Street


3.7         Results and Observations


3.7.1     The schedule of noise monitoring in reporting month is provided in Appendix E.


3.7.2     During the monitoring month, at KTD1a, non-project related construction activities at the nearby construction site and road traffic along Shing Cheong Road were observed in the surroundings. At KTD2a, road traffic along the Kwun Tong By-pass was observed. At KER1b, road traffic along Cheung Yip Street was observed. Major noise sources including noise emission from plant & PME and some other construction activities, travel of vehicles, loading and unloading of C&D waste were observed in the site. The above factors may affect the monitoring results.


3.7.3     No raining and wind with speed over 5 m/s was observed during noise monitoring according to the onsite observation. The weather conditions during the monitoring month are provided in Appendix K.


3.7.4     The noise monitoring data are summarized in Table 3.4. Detailed monitoring data are presented in Appendix G.


Table 3.4        Summary of Noise Impact Monitoring Results

Time Period

Leq (30min) dB(A)


Action Level

Limit Level

Noise Monitoring Stations




0700-1900 hrs on normal weekdays

68 - 73

58 - 69

61 - 66

When one documented complaint is received

75 dB(A)


KTD1a: Façade Measurement

KTD2a & KER1b: Free-field measurement (+3dB(A) correction has been applied)


3.7.5     No Action / Limit Level exceedance of location KTD1a, KTD2a and KER1b was recorded for construction noise in the reporting month.


3.7.6     The Action and Limit Levels for noise impact monitoring have been set are presented in Appendix C.


3.7.7     The Event and Action Plan for noise is given in Appendix H.



3.8         Comparison of Noise Monitoring Results with EIA Predictions


3.8.1     The noise monitoring data was compared with the EIA predictions as summarized in Table 3.5.


Table 3.5         Comparison of Noise Monitoring data with EIA predictions

Monitoring Station

Receiver Reference

Maximum Predicted Mitigated Construction Noise Level, dB(A)

Maximum Leq (30min) dB(A)

 In June 2018  














Maximum Predicted Mitigated Construction Noise Level extracted from Table 5.13 of EIA Report, EIAR-174/2013.


3.8.2     The impact noise monitoring results of location KTD1a, KTD2a and KER1b  in the reporting month did not exceed the Maximum Predicted Mitigated Construction Noise Level in the approved Environmental Impact Assessment (EIA) Report and no Action / Limit Level exceedance was recorded in the reporting period.