HVAC Acoustic Silencers & Sound Attenuators

Al Arabia sound attenuators are carefully designed to combat duct-borne and break-out noise. Galvanised steel outer casing is built to HVAC standard, perforated baffles are filled with odourless, incombustible, vermin-proof and moisture-proof inorganic sound absorbing material. Models: AR-SPD (short), AR-MPD (medium) and AR-LPD (long) in rectangular and circular form; circular attenuators (AR-RPD) from 300 to 1000 mm inner diameter and 435 to 1200 mm outer diameter. Splitters are minimum 24 gauge perforated galvanised steel filled with inorganic sound-absorbing material, standard splitter width 200 mm; casing minimum 20 gauge lock-formed galvanised steel. Acoustic infill is 48 kg/m3 rockwool with woven glass cloth facing, inert, non-flammable, non-hygroscopic, rot-proof and odourless; guaranteed against erosion up to 30 m/s air velocity and 121 C. Selection input data: design airflow, duct dimension, maximum permissible static pressure and sound power level. Joining by 30 mm slip-on flanges as standard; units above 2100 mm are supplied in multiple sections. Options include stainless steel 304/316 construction, epoxy paint or protective coatings, Ductmate / plain steel angle / slip flanges and access doors for cleaning. Standards & Certifications: ASHRAE, SMACNA, DW 144, ASTM A653, ASTM E84, ASTM E136, UL 723, NFPA 90A, NFPA 255, ASTM C1071, ASTM C423, Class 0 Building Regulations Typical Applications: plant room ventilations, fans and blowers, air-conditioning installations, cooling towers and chiller yards, power generation equipment, acoustic enclosure ventilation, AHUs / FAHUs, mechanical rooms, axial fans, residences, offices, hotels and hospitals noise criteria Key Differentiators: SPD / MPD / LPD model range; perforated baffle construction with 48 kg/m3 rockwool; up to 30 m/s velocity rating; Low-leak mastic-sealed casing; modular construction over 2100 mm; circular (AR-RPD) and rectangular families; acoustic infill tested to E84 / UL723 / C423