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Risks of optimising the Kilde 67 130 calculations in SoundPLAN
Asbjorn Hansen · Acoustics 2025 · Aug 2026
Many existing environmental approvals and licence conditions in Australia specify noise limits as an A-weighted 'average maximum' or 'LAmax,adj,T'. These descriptors originated in an era when analogue sound level meters were used and compliance was assessed by observing and informally averaging meter needle peak excursions. Modern digital sound level meters do not reproduce that observational process directly, and practitioners have commonly adopted the LA10 despite it being a time-exceedance percentile rather than an average of maxima. This paper presents the Average Maximum Sound Level (LAFmax,T), a repeatable empirical method for calculating the arithmetic mean of maximum levels over consecutive time intervals. The method provides a practical and repeatable approximation of the historical “average maximum” concept, reduces subjective variability, and offers a more appropriate legacy-assessment descriptor than LA10 in environments characterised by recurring maxima. A formal technical specification, ILTS-AC-001:2025, has been developed to support consistent implementation.
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Comparison of data transmission protocols for remote and real-time environmental monitoring
Ben Hall · Acoustics 2024 · Aug 2024
Environmental monitoring systems, particularly those involving remote sensors, rely heavily on efficient data transmission protocols to deliver real-time information for centralized analysis. This paper provides a comparative analysis of six key data transmission protocols—MQTT, HTTP, FTP, WebSockets, RPC, and WebDAV—assessing their suitability for remote and real-time environmental monitoring applications. The comparison focuses on four critical factors: connection overhead, latency, power consumption, and connection stability. Our analysis reveals that MQTT and WebSockets are the most efficient choices for real-time, low-power applications.
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Review of audio compression formats for post-processing
Ben Hall · Acoustics 2024 · Aug 2024
In this paper we investigate the impact of audio compression on the analysis of noise metrics using sound level meters. Various audio compression formats, including MP3, AAC, Ogg Vorbis, Opus, FLAC, ALAC, WavPack, and Speex, are applied to a series of test signals. Key noise metrics such as Leq, Lmax, Lmin, SEL,, statistical percentiles and 1/3 octave band analysis were compared.
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Limit of predicted road noise emissions due to traffic constraints - Part 2
Ben Hall · International Congress on Acoustics 2010 · Aug 2010
There is a limit to the number of vehicles that can travel on a road section per hour. Vehicle speed will decrease as the road becomes congested. In Queensland, road traffic noise emissions are based on the Calculation of Road Traffic Noise method (CoRTN). This method is dependent on both traffic volumes and speed, among other parameters, however in the current calculation method, speed is assumed to be constant. By incorporating the inherent traffic speed constraints a more accurate method of calculating the L10, 1hr is obtained.
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Limit of predicted road noise emissions due to traffic constraints
Ben Hall · Acoustics 2009 · Nov 2009
There is a limit to the number of vehicles that can travel on a road section per hour. As the traffic numbers increase, the traffic speeds decrease. In Queensland, road traffic noise emissions are based on the Calculation of Road Traffic Noise method (CoRTN). This method is dependent on both traffic volumes and speed, among other parameters. This paper presents a method for determining the upper limit of noise emissions from a road string, based on the CoRTN method. It is shown that there is point where due to the higher traffic volumes, there is a reduction of vehicle speed, causing the calculated noise emissions to decrease. These results have implications for the mitigation requirements for high traffic volume roads.
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Calculation of overall community noise impact due to a change in noise source emissions
David Davis, Ben Hall · Acoustics 2008 · Aug 2008
Calculation of overall community noise impact due to a change in noise source emissions