KENNEL DESIGN - NOISE

David Key

UNIT OF NOISE MEASUREMENT

Noise is measured in decibels (dB). The scale for this is logarithmis; this means that 90dB is ten times the intensity of 80dB and a hundred times the intensity of 70dB. An increase of 3dB doubles the sound intensity, so that 87dB is twice as noisy as 84dB. To put this into some context, a normal office environment is approximately 55dB.

NATURE OF NOISE

Sound is the transmission of vibrations at different frequencies; noise is defined as unwanted sound. The ear is a pressure sensitive mechanism, detecting small changes of pressure over a wide range of frequencies. The frequency of a sound is the rate at which it oscillates; this is expressed in Hertz(Hz). Although able to detect sounds in the range of 20-20,000Hz the ear is most sensitive in the 500-5,000Hz.

Dogs are most sensitive to sounds in the frequency range from 500 to 16kHz

REVERBERATION TIME

This is the time for a sound to decay to 60dB. Kennels by their nature have poor acoustic properties; hard, smooth surfaces do not absorb noise, therefore any noise generated tends to reverberate inside the building. The longer the reverberation time the more uncomfortable the building will be. For offices a comfortable working environment is considered to be 0.4-0.6 seconds, sports halls and swimming pools can be as long as 4-6 seconds.

LEGAL STATUS

Until recently it was generally accepted that kennels are noisy places and that was just another part of being a kennel owner. However, this approach is no longer a valid reason for not looking at these issues and how they could affect our business. The two main issued that are associated with noise are:

1 Environmental Protection Act 1995

2 Health & Safety At Work Act 1994

Although greater details of the legislation will be dealt with in a later issue it is worth looking at how they could affect you.

ENVIRONMENTAL PROTECTION ACT 1995

When an alleged statutory nuisance is made to the local council they are duty bound to investigate the complaint. In doing so they will make an objective assessment of how the nuisance affects the complainants' normal enjoyment of his/her property. Account is taken of several factors such as the level of noise, its regularity, duration, background noise levels, time of day etc. Although the number of complainants has a bearing on the validity of a complaint, a statutory nuisance can exist even if there is only one complainant.

The fact that the complainant may have only recently moved in the locality has no bearing on whether a statutory nuisance exists.

Once the local authority is satisfied that a statutory nuisance exists it is obliged to serve an abatement notice either prohibiting its occurrence or specifying the measures that must be taken to restrict its occurrence.

In the case of industrial, trade or business premises the person on whom the noitice is served may appeal on the ground(s) that the best practicable means (BPM) were used to prevent, or to counteract the effects of the nuisance.

Most local councils and kennels owners are not aware of the measures that can be undertaken to try and reduce the amount of noise coming from their site. Generally, if you want to continue to operate from your site the measures required to satisfy the local authority will take many forms; there is not one single course of action that will reduce the noise levels.

HEALTH & SAFETY AT WORK ACT 1994

The other issue that is often overlooked is that of staff welfare. Due to the potentially damaging effects high noise levels can have on the human ear it is something not be taken too lightly.

In the age of insurance companies who will undertake a potential claims case for "no fee", it is all too easy for a kennel owner to be faced with a claim from a former employee, sometimes going back over several years for loss of hearing due to dogs barking.

MAXIMUM EXPOSURE

Due to the potentially damaging effects of high noise levels on the human ear a series of "action levels" have been introduced. This is a system of measuring noise levels at certain decibel levels, which you are duty bound to respond. The levels are:

Level 1 - Establishes a daily personal noise exposure of 85dB. (Ear defenders should be worn at this level.)

Level 2 - Maximum exposure of 90dB. (Noise reduction measures should be implemented and ear defenders worn.)

Level 3 - Peak action level of 200 pascals.

Note - A Pascal is a measurement of sound pressure. Due to the small scales used ie 0 dB = 20 millionths of a Pascal the dB scale is more often used.

From my own studies using a basic hand-held noise meter it is not uncommon to find noise levels in the range from 85dB to 110dB. As the level at which it is deemed noise is a hazard to human hearing is 90dB and the threshold for pain is 120dB it is obvious that the range found in most kennel situations is at a level where action should be undertaken.

ANIMAL WELFARE

The other issue that is often overlooked is that of animal welfare. It is generally recognised that dogs have far superior hearing to humans; in fact they can detect sounds up to four times as quiet as humans. A noisy building that has long reverberation times has a detrimental affect on the dogs with increased stress levels ad disease. A relaxed, stress-free dog is far happier and is easier to care for; does not tend to go off its food or suffer from minor problems. A building with good acoustic properties and a relaxed atmosphere can go a long way to provide this.

WAYS OF REDUCING NOISE

The installation of an acoustic ceiling will greatly improve the quality of the acoustics within the building. A suspended acoustic ceiling is not more costly than plasterboard with a 2mm plaster skim and decorated with paint.

Kennel Design - Try to avoid long buildings with kennels either side of a central corridor. Even if the building is sub-divided into section, the fact that you have to walk down the full length of the corridor causes great excitement to the kennelled dogs.

Try to use solid concrete block partitions rather than all metal sheet. The noise generated from full height metal panels will add to the overall problem.

Try to design your site so that you don't have to walk past all of the dogs to gain access to external exercise enclosures. Again, you are loking at ways to reduce the amount of "negative" excitement to the dogs in their kennels that can see other dogs running free but cannot join in with the games.

Try to keep ancillary activities separate from the main kennel duties, eg free running exercise runs, free access to visitors to all of the site.

If you have covered exercise runs, look at installing acoustic tiles under the roof sheet. Not only will this reduce the amount of solar gain from the sun during a summer's day it will help reduce noise levels.

For particularly noisy sites some consideration might have to be given to installing acoustic fences to help deflect any noise coming from the site and also to help absorb it. Products such as Torvale's Woodcemair are extremely useful for such situations.