ASD GS Electrical C10.7.2 (c)
Noise level shall not exceed 65 dBA measured at 1 m from the fan.
Air extraction (Air Out)[Below video reading]Operation:45dBA ; Background:36.5dBA

Air intake rate (Air in)[Below video reading]Operation:45dBA ; Background:36.5dBA

Take off filter before measuring air speed rate.
ASD GS Electrical C10.7.2 (h)
Easy assembling/dismantling to facilitate servicing and maintenance work.
ASD GS Air-Conditioning C3.21 (b)
The exhaust fan shall be completed with a safety front grille at suction side

ASD GS Electrical C10.7.2 (b)
The exhaust fans (Air out) shall be capable of providing 0.06m³/s air extraction rate
[Below video reading]3.5m/s x 3.1416 x (150/1000/2)^2=0.062m³/s

Air extraction rate (Air out, fan anti-clockwise) is similar to Air intake rate (Air in, fan clockwise), by the same motor.
[Below video]

Air intake rate (Air in)
[Below video reading]3.5m/s x 3.1416 x (150/1000/2)^2=0.062m³/s

ASD GS Electrical C10.7.2 (b)
The exhaust fan shall comprise an electrically operated back draught shutter assembly.
ASD GS Air-Conditioning C3.21 (b)
Electrical operated shutter blades, covered by internal grilles, shall be overlapped and interlocked for maximum back-draught protection.

Other governmental requirements
EMSD Supply and Installation Contract Requirement
Noise level shall not exceed 40 dBA measured at 1.5 m from the fan.
[Video reading]Operation:39.5dBA ; Background:36.5dBA

SWD and HAD Requirements for Fresh air intake (Air in) speed With Filter for licensing premises
Classroom, Elderly Rehabilitation Centre, Elderly Home, Bedspace Apartments, Club, Hotel and Guesthouse
[Video reading]3.4m/s x 3.1416 x (150/1000/2)^2=0.06m³/s [Comply with ASD GS 0.06m³/s]

Air extraction rate (Air out) speed With Filter
[Below video reading at Front & Back] 2.8m/s(Front-For reference) & 3.8m/s(Back) x 3.1416 x (150/1000/2)^2=0.067m³/s [Comply with ASD GS 0.06m³/s]