Based in Pretoria, Enviro Acoustic Research (“EARES”) started in 2007 with the objective to become the foremost Environmental Noise Consultant in Africa. We aim to assist our clients in accurately describing existing ambient sound levels, quantifying the magnitude and extent of their noise impact to define the significance of their environmental noise impact.
Ambient sound levels are measured using best international practice (considering local regulations and guidelines), potential noise sources are identified and discussed with the client, and careful noise modelling is to define noise levels which are illustrated using aerial images to allow the compilation of a concise specialist report. Where required, future noise monitoring and appropriate and cost-effective solutions are included to manage and control the potential noise impact.
Since starting in 2007, EARES has assisted more than 60 clients (Consulting Engineers, Environmental Consultants, Industry, Mining, Town Planners, and private clients) with more than 400 Environmental Noise projects in SAC. While we only specialize in Environmental Noise and Vibration, we closely work with specialist companies in Structural and Architectural Acoustics.
Noise Impact Assessment and Reporting
The Environmental Noise Impact Assessment report is the cumulation of the experience and knowledge of the author(s). It finalizes the outcome from the baseline noise monitoring, the results of the noise propagation modelling, the assessment of the noise impact as well as appropriate monitoring, mitigation and management measures.
It is critical that such a report complies with the latest and most appropriate legislation (not to follow the National Noise Control Regulations when the project is located in the Western Cape, etc.), legislatively stipulated procedures (Appendix 6 or GNR320) as well as the requirements of SANS 10328:2008.
While this sound simple, we have reviewed (external) reports where the wrong legislation was followed, the wrong procedures were used or the report does not consider the SANS 10328:2008 methodologies. Should such a project face an appeal or other legal challenges, this would be the starting point for any attack.
It is thus important that the client and Environmental Assessment Practitioner select a specialist that would follow the correct process and procedures. While legal challenges are relatively rare, using a noise specialist that does not comply with best practices could result in a very expensive error.
Unless specifically required by the client, EARES would advise and follow the latest legislative requirements, using a template based on the SANS 10328:2008 methodologies. All projects are approached from the point that they may face a legal challenge and care is taken to ensure that our noise study will not be used as the reason why an appeal or legal challenge is successful.
Legal and Technical Review
This could be a simple review, only considering the content of a noise study (done by a different company) in terms of legislative requirements and the SANS guidelines, or a full review which could include considering the accuracy of noise modelling. A legal and/or technical review may be required for a number of reasons, including:
- As part of the legal team during an appeal, tribunal, and legal proceedings. While relatively rare, appeals and objections to a project is a reality, and it is surprising how many specialist studies do not comply with the latest regulations (or the prescriptions of SANS 10328:2008). Such documents are considered fatally flawed. We therefore take considerable care to ensure that all our documents comply with the latest and correct regulations as well as the SANS 10328:2008 prescriptions.
- For a client concerned about the adequacy of an external report to face public scrutiny. You do not what to submit an EIA or specialist study that is technically incorrect, or worse, fatally flawed, as any delays could result in significant costs, and even jeopardize the viability of a project. In addition, operational decisions must be taken, and incorrect modelling could result in significant cost implications for various reasons.
Sound and Noise Measurements
Correct and accurate measurements are more than taking a sound level meter, pointing it in a direction, and pressing a button.
Accurate measurements depend on understanding the purpose of the measurement, selecting the appropriate instrument, using the correct settings (requiring an understanding of reference periods, measurement periods, time-weighting, frequency weighting, etc.), using applicable calibration protocols, using proper measurement protocols (considering the measurement environment, purpose of measurement etc.).
After the measurement, the data must be processed and analyzed to provide truthful and useable information. Depending on which instrument is used, a typical 10-minute measurement could generate more than 100 unique readings. Over a 2-day period (the default used by EARES) one can have more than 200 datasets, each containing more than 100 readings.
Processing, analyzing, and understanding the resulting information require training, significant experience, and knowledge.
When selecting EARES as your service provider, clients can trust that EARES has the understanding, knowledge, and experience to correctly measure, process, analyze and present the resulting information in a manner that authorities and other stakeholders can understand.
Noise Audit and Monitoring
Noise audit and monitoring are normally completed to ensure legal compliance, either in terms of Regulation 6 of the Noise-Induced Hearing Loss Regulations (GNR 307 of 2003), or as required by the Environmental Authorization or commitments defined in the Environmental Management Programme of a client.
Occupational services would include:
- Identification of significant noise sources.
- Delineation of compulsory hearing protection areas.
- Detailed or preliminary level noise surveys.
- Equipment noise compliance testing.
- Defining the sound power emission levels and characteristics.
- Workplace noise management plans.
- Noise control and mitigation recommendations.
Environmental services would include:
- Identification of potential noise-sensitive receptors.
- Identification of noise sources.
- Selection of measurement locations and design of noise monitoring programs.
- Equipment noise compliance testing.
- Estimation of equipment sound power emission levels, or the sound power emission levels associated with activities.
- Noise control and mitigation recommendations.
- Short to long-term noise level measurements.
Noise Propagation Modelling
Accurate noise modelling depends on a number of factors, including:
- Understanding of the equipment and activity, and where noises will be generated.
- Precise identification of noise sources, their significance, and their sound power emission characteristics.
- Selection of appropriate input parameters, including noise sources and their operational cycles, atmospheric absorption, surface characteristics, and topography.
- Use of an accurate and appropriate noise propagation algorithm as well as understanding the benefits and disadvantages of these algorithms (whether using a basic noise model or commercial package).
- Experience gained through years of doing noise measurements at existing projects to understand the noise levels that may be expected from such a project.
EARES, therefore, spends significant time developing a noise model to ensure that the resulting noise rating levels are applicable to the project. Over-estimating noise levels will result in significant cost overruns in implementing noise control or other mitigation measures.
More dangerous would be the under-estimation of noise rating levels, potentially resulting the noise complaints, administrative directives, and even legal challenges. This could result in a process requiring expensive retro-fitment or changes, the relocation of the process, or even the termination of a project.