An anechoic chamber is a silent room used for carrying out standard acoustical tests. ‘An-echo-ic’ means without echoes. As the chamber sounds very ‘dead’, measurements are not influenced by the room surfaces.
Our anechoic room is one of the largest in the UK. The room is lined with sound absorbing polyurethane foam wedges. This creates 'free field' conditions with no sound reflection from the walls, floor or ceiling.
Uses include measuring:
the sound power of a machine to British, European and international standards
microphone and loudspeaker frequency responses
sound levels and spectra of alarm sounders such as smoke alarms, train horns and fog horns  
We've recently installed new polyurethane wedges along with a wire-mesh or ‘trampoline’ floor, and removable load-bearing floor panels. 
Part of:
Technical specification
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built as a single-skin concrete box
acoustically isolated from the rest of the building by an air gap
305mm thick reinforced concrete walls to insulate against external noise 
 Wall lining 
approximately 3209 non-flammable open-cell polyurethane wedges
extends 1.2 metres from the walls, floor and ceiling
free field conditions exist at frequencies above 70Hz 
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without wedges: 9.15 metres wide, by 9.15 metres long, by 7.32 metres high
volume: 611 cubic metres
usable space between the wedge tips: 6.70 metres wide, by 6.70 metres long
height from the load bearing floor to the ceiling wedge tips: 4.86 metres
usable volume: 218 cubic metres
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main access through a pedestrian door: 1.29 metres wide, by 2.10 metres high
alternative access for larger items through double doors: 2.0 metres wide, by 2.4 metres high  
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A permanent wire-mesh floor can be walked on and will support a distributed load of 8 people. 
We can also install a load-bearing floor. It is made of removable glass-reinforced plastic grid panels above the wire-mesh floor.
The panels, supported on removable posts, are 600mm square. We can install as many panels as needed to support equipment under test or microphone stands. The floor can take a spread load of several tons.
A varnished chipboard flooring can be overlaid onto the load-bearing floor. This is useful when test standards need a ‘free field above a reflecting plane’ (hemi-anechoic conditions).
Control room 
There is a control room next to the chamber which allows laptops, instrumentation and equipment to be placed outside the chamber. Cable ports give access to and from the chamber.
Research
We use the anechoic chamber for University research. It's also used for commercial testing and consultancy.
We work with industry, the private sector, public bodies and government agencies in the UK and Europe.
We are part of the University’s Rayleigh Laboratories operated by ISVR Consulting.  Get in touch to find out more about our facility and how we might be able to work with you.
