title: A study of the influence of mounting conditions on the measured sound absorption in laboratory tests of suspended ceilings.
abstract: This letter presents the results of an investigation into the influence of mounting conditions on the measured sound absorption coefficients of a suspended ceiling specimen. A series of measurements and analyses were carried out using a fixed standard sample, varying independently different mounting parameters and introducing controlled leaks. A correction of room volume in the calculation of the sound absorption coefficients was also examined. The tests were carried out in accordance with the ISO 354:2003 standard (International Organisation for Standardisation, Geneva, 2003), using the type E mounting. The test specimen consisted of fiberglass wool panels covered with a plastic film. Some of the experiments resulted in no statistically significant alteration. This included, unexpectedly, the sealing requirements of E type mountings.
authors.affiliation: Institute for Technological Research, 05508-901, São Paulo, SP, Brazil.
authors.forename: Marcelo
authors.initials: M
authors.lastname: de Godoy
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Barry
authors.forename: Sylvio R
authors.initials: SR
authors.lastname: Bistafa