A sound attenuator is a lined duct section or silencer that reduces noise generated by HVAC equipment and airflow through ducting systems. These devices typically reduce noise levels by 10 to 20 decibels depending on frequency and design. Sound attenuators contain internal fiberglass or foam insulation that absorbs sound energy as air passes through the unit.
Noise Reduction Technology
Sound attenuators are effective at reducing mid to high-frequency noise, typically from 500 Hz to 4000 Hz. They are commonly installed on blower discharge lines, return air drops, and exhaust ducts to achieve acceptable indoor noise levels below 35-40 decibels. Larger diameter attenuators with greater length provide improved noise performance without excessive pressure drop.
Application and Performance
Sound attenuators are essential in residential, office, and healthcare facilities where noise control is critical. Typical units measure 12 to 36 inches in diameter with lengths ranging from 24 to 48 inches. Proper placement immediately after noisy equipment provides maximum attenuation while flexible ductwork connections further isolate vibration transmission to building structures.