أنشئ حسابًا أو سجّل الدخول للانضمام إلى مجتمعك المهني.
If it is a machine of more than 1200 CFM use sound Attenuator to achieve required NC level. If it is Lower Than 1000 CFM, design a ducting so that velocity will be low and even grill & diffuser size select higher side.