SoundScapeIssue 0211

SoundScapeIssue 0212The cost of poor acousticsPresenting MPs with the possible fi nancial implications of abandoning acoustic design is not just a tactical manoeuvre; negligent acoustic design in schools really has cost the UK dearly. For example in 2008, Bexley Business Academy had to spend £600,000 to fi x its acoustic problems, fi ve years after it had opened. The fl agship £31m academy, designed by Sir Norman Foster, was an impressive steel and glass structure. However, its open plan classroom design meant that sound washed around the building, having a detrimental effect on pupils' concentration. Other fi nancial concerns include the potential legal battles to be avoided. A teacher was awarded £150,000 last November by a local authority after suffering vocal damage from raising her voice too much in a noisy school environment. On top of all this, it can cost schools thousands of pounds in sick cover for teachers who have strained their voices.But the most important message that the IoA and ANC have been trying to communicate to ministers is that excessive classroom noise, combined with bad acoustic design, has a proven negative effect on children's' cognitive and learning abilities. Stephen Stansfeld, Professor of Psychiatry at the University of London, Queen Mary, has contributed to some leading studies examining the correlation between environmental noise and mental health. Working with a team of international scientists and psychiatrists he led the RANCH report on the effect of aircraft and road traffi c noise on school children, conducted at key locations across Europe. Speech intelligibilityThrough his work, Stansfeld is adamant that classrooms designed to high acoustic standards are essential. "It is very important because too much noise in the classroom can really interfere with children's cognitive processes," he argues. "Noise can vary, it may be noise from outside that penetrates into the classroom or it may be noise within the classroom - and if the classroom has a lot of hard surfaces they will amplify the noises and make things worse. Also, if a classroom has poor acoustic conditions, then speech intelligibility will be reduced - thus the pupils may not be able to understand the teacher so well, and not be able to pick up everything he or she says."For some tasks, however, it helps to have a little background noise. Stansfeld explains: "If you are carrying out a very simple and sort of vigilance-type task then often a little bit of noise tends to keep you awake, it tends to increase you're alertness. So some background noise can actually be helpful in that sort of setting. However, most of the learning tasks children are carrying out in schools are more complex."Of course, internal classroom babble is not the only noise that can affect children. For his work with RANCH, studying the effects of aircraft noise on children, Stansfeld and his team assessed 2,844 children attending 89 schools in the Netherlands, Spain and the UK. Their fi ndings proved that a rise in chronic aircraft noise caused impairment in reading comprehension and recognition memory. They also studied the effect of road traffi c noise on children, which was linearly associated with increases in episodic memory. External noiseThe RANCH study builds on previous research carried out in schools and homes located near airports. A study conducted in Munich in the 1990s, found that children living next to the city's main airport were less able to perform cognitive functions when living under the fl ight path. However, when the airport was relocated these children began to demonstrate normal cognitive abilities, while the children under the new fl ight path began to suffer.Ultimately, Stansfeld argues, it is simply better not to build schools at the end of runways in the fi rst place. "We found from studies at Heathrow, at Schiphol in Amsterdam and also at Barajas in Madrid, that aircraft noise had a kind of increasing linear effect on reading comprehension, so that as aircraft noise increased, reading comprehension got worse and that also seemed to affect a type of memory called recognition memory - where you are reading a story and later on you are asked certain questions, to test your recognition."It was this growing body of evidence which encouraged the Sweyne Park School in Rayleigh, Essex, in 2008, to take a risk and conduct their own acoustic experiment. By liaising with Essex County Council, a sound absorbing tile manufacturer and a handful of acoustic specialists, the team began treating various classrooms with acoustic tiling. At fi rst this was intended to just help the small percentage of deaf children at the school. However, after witnessing the success of this experiment and the increase in the deaf pupils' performance, the school decided to roll it out in other areas of the building. The results have been encouraging: busy classes are quieter, teachers are not straining their voices and grades have even risen. By fi xing acoustic tiles to the ceiling in Sweyne Park School and adding sound absorbent wall boards around the room, staff found that children's learning could be improved without paying through the roof