Table 3.3 Noise Monitoring Parameters, Duration and Frequency

Contract No.	Monitoring Stations	Parameter	Duration	Frequency	Measurement
ND/2019/01	CP-KTN NMS5	L10(30 min.) dB(A) L90(30 min.) dB(A) Leq(30 min.)dB(A) (as six consecutive Leq, 5min readings)	0700-1900 hrs on normal weekdays	Once per week	Free-field^[1]
ND/2019/06	CP-FLN-NMS1				Façade

Remarks:

[1]: Correction of +3dB (A) for Free-field Measurement.

[2]: A-weighted equivalent continuous sound pressure level (L_eq). It is the constant noise level which, under a given situation and time period, contains the same acoustic energy as the actual time-varying noise level.

L₁₀ is the level exceeded for 10% of the time. For 10% of the time, the sound or noise has a sound pressure level above L₁₀.

L₉₀ is the level exceeded for 90% of the time. For 90% of the time, the noise level is above this level.