CSIRO scientists have been testing wall insulation and glazing options in hopes of making the new Royal Adelaide Hospital the quietest hospital in Australia.
A team of scientists from the Commonwealth Scientific and Industrial Research Organization's (CSIRO) Melbourne acoustics lab have been working alongside façade manufacturer Yuanda and builder HYLC Joint Venture to test the materials that will be used for the 70,000 square metres of external windows in the hospital set to open in 2016.
“One of the major issues with the construction of this building is that there are helicopters landing on the roof,” said CSIRO project leader Christopher Preston.
While the helipad is be beneficial for patient transport, it poses an additional challenge for builders to meet the stringent sound proofing requirements set out by the South Australian government.
The hospital was adamant about noise from helicopters not disturbing the rest of patients which can lead to longer recovery times.
Preston says the volume of a helicopter landing or departing from 20 metres away could reach 100 decibels, not at all conducive to a peaceful place of recovery. A considerable amount of recent research has documented the negative effects of noise on patient outcomes.
“Whereas domestic buildings have single or thin double glazed windows, in this instance, triple glazing, very thick glass and very large gaps between the glass help provide acoustic insulation,” said Preston.
To test the window materials, a brick wall was custom-built between two cavernous sound chambers to hold the sample windows.
The CSIRO acoustic lab is one of the few Australian facilities equipped to perform the low frequency measurements for the window assessment.
With all other sounds eliminated, a standardised sound source generated noise in one of the chambers while the intensity of the sound and pressure levels were measured on the other side of the glass, showing the CSIRO team how well the glazing would perform with the noise of a helicopter.
“To ensure that all areas of the hospital meet the sound insulation requirements, a range of different window configurations had to be evaluated,” said Preston. “This meant the brick wall had to be knocked down and rebuilt about a dozen times in order to hold different façade elements.”
Results proved the effectiveness of Yuanda’s glazing systems to be in line with hospital requirements.
“We measured a whole range of different types of façade units that were ultimately used and intended to be used for the hospital and performed measurements to demonstrate that they could meet the requirements the contractors had been given,” said Preston.
The CSIRO’s Infrastructure Technologies group is renowned worldwide for having assessed some of the world’s most iconic building façades and in Australia for its work on the Sydney Harbour Tunnel and the Sydney Airport.
“We haven’t been involved in a project like this previously,” said Preston. “However, I do know that other hospitals under construction in the country are also looking at preventing helicopter noise, but I believe the Adelaide hospital will be the first to be constructed to this level.”
“It’s been a very great engineering challenge to actually achieve the high performance that the South Australian government has requested, but in the end this will be Australia’s quietest hospital.”