Abstract:
Sound breakout from rectangular HVAC ducts constructed of fiberglass duct board has been investigated. Duct sizes that were tested were 12x12, 12x24, 12x36, 24x36, and 36x36. All dimensions are in inches. Four duct lengths for each duct size were tested: 4, 8, 12, and 16 ft. The sound breakout values for the fiberglass duct board were compared to corresponding values obtained from similar sized rectangular sheet metal ducts. Major objectives of the study were to obtain duct transmission loss values for rectangular ducts constructed of fiberglass duct board, to compare these values with corresponding values obtained from similar sized rectangular sheet metal ducts, and to specify conditions in which rectangular ducts constructed of fiberglass duct board can be used in situations where the control of duct breakout noise is important.