Overview
ISO/TR 17534-3:2015 is a technical report from ISO that provides recommendations for a quality‑assured implementation of the outdoor sound propagation calculation method given in ISO 9613‑2. Intended as a method‑specific addendum to ISO 17534‑1 (software quality requirements and QA), this report supplies agreed implementation rules, a suite of test cases with detailed step‑by‑step results, and the forms needed for a software Declaration of Conformity (DoC). It helps ensure that acoustic modelling software correctly and consistently implements the ISO 9613‑2 engineering method for outdoor noise prediction.
Key topics and technical requirements
- Scope and normative references: Identifies ISO 9613‑2 and ISO 17534‑1 as essential references and clarifies terms and definitions used.
- Agreed additional recommendations: Minimum, transparent rules to reduce modelling ambiguity when replacing complex wave behaviour by ray paths (screening, diffraction, path selection).
- Specific algorithmic clarifications:
- Screening and ray‑path identification rules
- Calculation of path‑length difference (z) and related geometry handling
- Treatment of diffraction (including barriers on reflecting ground and lateral diffraction limits)
- Limitations on maximal possible barrier attenuation
- Handling of ground effects, elevated ground, and multi‑reflection (higher‑order reflections)
- Comprehensive test suite: A set of test cases (T01–T19 in the report) covering flat and varying ground, reflecting/porous ground, barriers (short/long), buildings of various shapes and receiver heights, and step‑by‑step and final result intervals to verify software results.
- Declaration of Conformity (DoC): Forms and guidance for software vendors to declare conformity of their product implementation with the recommendations.
Practical applications and users
- Acoustic software developers - implement and validate ISO 9613‑2 functionality in modelling tools and ensure traceable QA.
- Acoustic consultants and engineers - rely on validated software for environmental noise assessment, planning, and impact studies.
- Regulators and certification bodies - evaluate and accept software products based on the provided test cases and DoC forms.
- Quality assurance teams - establish automated test workflows using the detailed test suite to detect implementation errors or regressions.
Related standards
- ISO 9613‑2:1996 - Attenuation of sound during propagation outdoors (calculation method).
- ISO 17534‑1 - Acoustics - Software for the calculation of sound outdoors - Part 1: Quality requirements and quality assurance.
- ISO/TR 17534‑2 - General recommendations for test cases and QA interface.
Keywords: ISO TR 17534-3:2015, ISO 9613-2, acoustics, outdoor sound calculation, noise prediction software, software quality assurance, test cases, declaration of conformity.