Acoustical Society of America
ASA/EAA/DAGA '99 Meeting
Lay Language Papers

Are Our Hospitals Too Noisy?

Eduardo Bauzer Medeiros -, fax: (+) 55- (0) 31- 4433783
Departamento de Engenharia Mecanica da UFMG Av. Antonio Carlos 6627 31270-901, Belo Horizonte, MG, BRAZIL

Ivan de Azevedo Camelier
Departamento de Ciencias Aeroespaciais Universidade da Beira Interior, Portugal

Popular version of paper 3pAAb4
Presented Wednesday afternoon, March 17, 1999
ASA/EAA/DAGA '99 Meeting, Berlin, Germany

It is a well known fact that noise is annoying. The inhabitants of major towns often complain about noisy parties or neighbours which are disturbing them. There is also now a growing awareness that high noise levels can seriously affect the hearing, even causing permanent damage. In fact, existing noise regulations have improved our lives. Vehicles are a lot quieter now and your employer has to provide a healthier (noisewise) environment for you. Unfortunately, awareness is not sufficient to establish healthier behaviour, and a large number of people are still becoming deaf because they didn't believe (literally) what they heard. What can you do with adolescents adjusting their walkmen systems too loud, or workmen in noisy industries who believe they have "become immune" to noise, and consequently do not follow proper procedures? Early education, as it happens in most cases, is probably the best way to deal with this problem, which affects the nearly the entire population.

Noisy environments can also introduce other less well-publicised health problems. It is a proven fact that moderately high noise levels may not only damage your ears but also increase your blood pressure, raise your cholesterol levels, increase your pulse rate, disturb your breathing and introduce a variety of other more subtle effects. In fact noise can disturb your mental activities and provoke the liberation of hormones, therefore affecting your complete health. It is curious to observe how some people even become "noise addicts" and they experience (for example) a pleasant feeling listening to very loud music, a fact which is associated with the conditions just mentioned.

Existing legislation is probably adequate to deal with higher noise levels. However it does not always cope with other less obvious cases such as a condition broadly described as "stress" which is closely associated with our brain activity, and which may vary according to the noise level. Perhaps the more subtle of these modifications is associated with sleep-related diseases. Our sleep is divided into a series of different phases, each one of them performing a certain function required to keep our bodies mentally and physically sound. Slightly more noisier environments can disturb our sleep, and increase our stress.

It is also a proven fact that stress and other physically-related factors may affect our resistance to diseases and infections, and retard the recovery of an illness. As a consequence, noise-related factors may affect our health far more than we could imagine. One does not need to be concerned only with deafness, but also with noise related stress, and other closely associated conditions. Hospital patients are particularly affected, since they are already outside their preferred environment, are not free to do what they want, and are obviously already less healthy and strong.

The main origin of noise disturbance in new hospitals located inside densely populated areas can be usually associated with vehicular traffic. In fact it can even be said that hospitals provide a conflicting requirement for the designer, as far as traffic is concerned. A hospital needs good and fast road access, but you have to keep the patients away from traffic noise. Location is another problem. Hospitals providing emergency services have to be located near where most people live, where there is very often intense vehicular traffic. There is usually a pressure from several lobbies to increase slightly the permitted noise levels in major roads, because it is difficult to provide adequate traffic and goods flow in the presence of severe noise restrictions. However, there is clear (measured) evidence that many major hospitals located inside large cities operate with inadequate noise levels. In fact the community should press for even more restrictive noise levels in the vicinity of hospitals. A speedier recovery for a given patient is not only important because of the patient's well being. It also means that the whole system can be run more inexpensively.

There are a variety of means to control noise. Many of the more common noise control procedures, such as enclosing an area, can not be used in hospitals, because of infection control procedures. Other measures such as "noise barriers" are not very effective for most town hospitals, because they require unacceptable dimensions. Generally speaking, in any noise control method it is useful to employ a combination of strategies. Traffic flow control is, however, an essential factor. The problem is complex and demands the close attention of the city planners. methods must be devised that decrease traffic, reduce its speed ,and make it run smoother, by providing diversion and making adequate use of traffic lights and other indications mechanisms. Heavy vehicle traffic should also be lessened, as it tends to be disproportionately noisy.

Proper hospital location, whenever possible, is the best way to achieve more suitable conditions. It is also clear that one has to observe not only the present situation but also the expected effects resulting from the complete city planning; including such factors as occupation laws, planning of new roads and the like. It should be kept in mind that corrective measures are always harder and do not always producie satisfactory results.

Finally, it is up to us to guarantee better standards to ourselves. We have to maintain our awareness of potential but not obvious noise-related problems, and demand a similar position from our administrators. Far sighted planning and legislation shall hopefully provide, among other things, better hospitals and better living conditions.