Emergency Generator Sets
(A) Problems
Air-borne Noise
• Noise generated from emergency generator sets may cause disturbance to nearby residents. It mainly comes from the air flow noise resulting from air turbulence at the air intake and exhaust, compressor noise of turbocharger, combustion noise of internal combustion engine, fan noise and mechanical noise from engine and generator (see Figure 43).
Structure-borne Noise
• Vibration from an operating generator set may be transmitted to the interior of the building through building structure when the generator set is directly mounted on a supporting structure without proper isolation. The vibration transmitted may activate the building structure to generate noise which causes noise disturbance to residents inside the building (see Figure 44).
(B) Practical Remedies
Air-borne Noise
• Locate the emergency generator sets inside a plantroom (see Figure 45 and Figure 46) with thick walls, sound adsorption materials, soundproof door and silencers at air inlet and outlet.
(Noise Reduction Up to 30 dB(A))
Structure-borne Noise
• Provide inertia blocks and vibration isolators to support an emergency generator set (see Figure 47), thereby isolating from the building structure.
• Provide flexible connectors between the machine and associated pipework to avoid structural vibration transmission (see Figure 47).
• Use vibration isolators for attaching pipes to walls, ceilings or floors.
(Noise Reduction Up to 20 dB(A))
