Noise Facts

The National Picture

It is difficult to get an accurate picture of the total number of noise complaints reported in England, Wales and Northern Ireland. The latest figures for 2008-09 represent data received by 186 of the 402 (46.3%) Local Authorities.

The total number of noise incidents complained about were 120,082 for the 46.3% of authorities who responded. The pie chart below shows how they were divided and that the majority of complaints were about domestic noise (72%). Given that these are returns from approximately half of all Local Authorities in England, Wales and Northern Ireland, if you double the figure it gives a rough idea of what the National picture might look like.

What's happening locally?

This pie chart details the number of noise complaints in each noise source category received by Elmbridge Borough Council for last year ending 31/3/2011. The total number of complaints for last year was 872.

This pie chart details the number of noise complaints in each noise source category received by Elmbridge Borough Council for last year ending 31/3/2010. The total number of complaints for last year was 857.

A few technical facts about noise

Noise can be defined as 'unwanted sound'.

Sound is defined as any pressure variation in air, water or other medium that the human ear can detect.

How is sound heard?

Sound is heard because particles (in any medium) have been caused to vibrate by a sound source, e.g. a loudspeaker or your voice. The vibrations spread out from the source, like ripples in a pond, and are detected by the ear.

Note: sound can travel through solids, liquids and gases.

How is sound measured and how is it perceived?

Sound intensity (loudness or volume) is measured in Bels after Alexander Graham Bell. For convenience, we work in Decibels (dB) i.e. one tenth of a Bel, and a logarithmic measurement scale. As it is a logarithmic scale it does not work in the same way as an arithmetic scale. For example:

A special weighting is added called the 'A weighting' which approximates to how the human ear hears sound, denoted as dB(A). So measurements using a sound level meter set to measure dB(A) is representative of what the human ear would hear.

The human audible range is from the threshold of hearing at 0 dB to the threshold of pain at 140 dB.

The smallest perceptible change in sound level is 1 dB, although this will normally only be noticeable in laboratory conditions. A level increase of about 8 to 10 dB is required before the sound will appear significantly louder to the listener. A difference of 10 dB(A) is perceived as a doubling of loudness and as the table below shows this level of difference is significant.

Now a bit about frequency...

Frequency can be defined as the rate of repetition of a sound wave and is measured in hertz. When you hear a sound, it will normally consist of lots of sounds across a whole range of frequencies, Humans can normally hear sounds between 12 Hertz (Hz), which is very low frequency to 20,000 Hz, which is very high frequency, although everyone is different and hearing will change with age. Other species will have different hearing ranges, for example dogs can hear frequencies higher than 20,000 Hz, which is why they are able to hear dog whistles, when humans cannot.

Low frequency sounds have the most energy and the sound waves will easily travel over a long distance and will penetrate through materials. This is why, if your neighbour is playing music, you may be able to hear bass beats through a party wall but you may not be able to make out the tune or words. High frequency sounds have less energy and the sound level will reduce significantly over distance and they are not able to penetrate most materials. A very high frequency noise would not even be able to travel through a sheet of paper.

From the bar chart below detailing the breakdown of noise complaints received at Elmbridge Borough Council during 2009-2010 you can see that loud music and party noise account for a large proportion of all complaints about noise. Loud bass beats are commonly reported as being particularly annoying by those living in flats and attached houses.

What causes noise to be annoying?

There is almost always some noise in our environment, e.g. the television or radio on in your home, or conversations and printer noise in an office, and most of the time this will not result in annoyance. These are generally accepted as being everyday living noises and in most cases will often go unnoticed they are part of your noise background.

However if there is a particularly loud noise that stands out above the background noise level or there is a particularly annoying feature such as high pitched whine then this is more likely to cause annoyance. Remember people can't turn their hearing off and because the noise is above the background level it is more likely to attract your attention. Most people would not be annoyed if they could hear some of their neighbour's music or television inside their property for short periods during the daytime, but if they can hear it in the evening or during the night when they are trying to relax, this is more likely to cause annoyance.

Its difficult to give a definite description of what causes noise to be annoying, since noise behaves in complex ways and background levels vary by location and time of day.

The Role of an Environmental Health Officer

Environmental Health Officers (EHOs) are tasked with investigating noise complaints and they use their knowledge and experience to assess whether noise amounts to a statutory noise nuisance under the Environmental Protection Act 1990.

Statutory nuisance is more than a mere annoyance and will have a significant impact on the health and wellbeing of anyone affected. Some people may find a noise annoying but it might not be a statutory nuisance in the eyes of the law. Individual sensitivities cannot be taken into account and the role of the EHO is to act as the average, everyday person or "the man on the Clapham omnibus" in assessing |whether there is a statutory nuisance.

EHOs might ask people suffering from excessive noise to complete diary sheets of noise incidents, make visits to the area where the noise is occurring or use sound recording equipment as part of their investigations.

The EHO will try to work with whoever is responsible for the noise to resolve any noise problems informally, however, where this approach fails, a legal notice called an Abatement Notice may be served. It is a criminal offence not to comply with such a notice and the Council may take formal action.