Introduction

Many types of noise source must be dealt with under the Noise Control Act. Since this includes any type of noise, it must also include noise of people as well as mechanical noise. As part of the approval process for a Child Care Centre in Sydney, a Noise Impact Statement was requested by the local Council. The Child Care Centre operators had designed the Centre to have a maximum capacity of fifty to sixty children between the ages of two and five. These were to be accommodated in the two main rooms of the Child Care Centre.

Investigation

The only noise associated with the Child Care Centre were identified as vehicle noise, as parents dropped off and collected their children, and the sounds of the children themselves.

The vehicle noise was not considered a problem as the cars were infrequent, of limited duration, and few in number. Due to local speed control measures traffic speed was limited, and by the very nature of the centre and its function, vehicle movement was limited to daylight hours when other suburban traffic movement would be an expected and unobtrusive part of the local environment.

The area of greatest concern was potential noise generated by the children at play or in organised activities within the Centre.

Architectural and site layout drawings were examined to assess the expected distance attenuation, barrier attenuation, sound transmission loss values, and the sound reducing effect of internal furnishings. To this was added the expected sound power frequency spectrum of fifty children at play.

It was concluded that organised activities could occur at the sides of the building, and less supervised activities at the rear where it was further away from the neighbours. With hard wearing carpet throughout and with gap free side fences, it was expected that combined noisy activities could be permitted inside as long as no more than one side door or window was fully open at any time. The report was submitted to Council and accepted on the condition that the operator comply with the recommendations of the noise impact study.

Twelve months later, the Child Care Centre operator requested a Compliance Report to be prepared immediately prior to opening the Centre.

When the premises were inspected and it was found that the operator had deviated significantly from the original recommendations. As well as ignoring a number of the recommendations, there was poor workmanship throughout (doors which didn't seal; light weight glazing where the original drawings indicated heavy glazing; solid gap-free side fences which become wooden paling fences with gaps between the palings). The internal flooring had changed from full carpet, to half carpet and half cement. Instead of a simple Compliance Report to confirm that the recommendations had been met and that all was well, the entire Centre had to be reworked.

This time round it had to be recommended that doors and windows be fully closed at all times to prevent noise intrusion into adjoining homes. Immediately it became apparent that the building would require forced ventilation, if it were to be usable summer or winter. With forced ventilation came fans; with fans came fan noise; with fan noise came fan noise silencers, compounding the cost of compliance with each step. The Child Care Centre was finally opened on time, but with the addition of a fully ducted air conditioning system.

Conclusions

Receiving the Approval at the start of a project, does not automatically mean the Approval is forever, never again be reviewed. Ignoring or discounting the recommendations of the original technical reports, the operator risks either loosing their Approval, or the sudden imposition of expensive changes at the last minute to keep it at a time when the project is "complete" but not yet earning. By either complying to the original recommendations or having any changes reviewed along the way expensive rectification at the end of the project can be avoided or at least finances can be adjusted to compensate.

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