ISO 6395:2008

Overview

ISO 6395:2008 specifies a repeatable test method to determine the A-weighted sound power level emitted to the environment by earth-moving machinery operating under dynamic test conditions. It gives procedures for measuring noise from machines defined in ISO 6165 (e.g., excavators, dozers, loaders, rollers) using a simulated dynamic sequence to produce representative, reproducible sound power data for compliance, product comparison, and noise-reduction work.

Key Topics and Requirements

• Scope and definitions: Defines key quantities such as time-averaged A-weighted sound pressure level (LpA,T), A-weighted sound power level (LWA) and the machine basic length (l) and machine centre point used to position the measurement hemisphere.
• Instrumentation: Recommends integrating/averaging sound level meters (IEC 61672-1 class 1 preferred) capable of the required averaging and data acquisition.
• Test site and environment:
  • Three allowed ground types: hard reflecting plane (concrete/asphalt), combination reflecting plane + sand, and all-sand plane.
  • For hard reflecting planes, environmental correction K can be assumed ≤ 0.5 dB and set to 0 dB when obstacles are negligible. For sand sites K must be determined and applied.
  • Requirements for background noise correction, climatic conditions, and instrumentation operating limits are specified.
• Measurement geometry:
  • Use a hemispherical measurement surface with microphone positions defined relative to the basic length and machine centre point.
  • Size of the measurement hemisphere, microphone placement and machine positioning are standardized to ensure repeatability.
• Machine operation:
  • Procedures for engine speed, fan speed, travel modes and required attachments (manufacturer’s production configuration) are provided to simulate dynamic operation.
• Calculation and reporting:
  • Step-by-step measurement procedure, calculation of LWA including corrections (environmental and background), uncertainty declaration and reporting format are specified.
• Annexes: Normative annexes cover basic length and machine-specific test details (excavators, dozers, loaders, dumpers, graders, rollers, etc.), plus guidance and declaration templates.

Applications - Who Uses ISO 6395:2008

• Manufacturers of earth-moving machinery for type testing, compliance with noise regulations and product data sheets.
• Test laboratories and certification bodies performing sound power measurements under dynamic conditions.
• Environmental and occupational noise engineers using measured LWA values for site planning, mitigation and comparative assessments.
• R&D teams conducting noise-reduction design and verification.

Related Standards

• ISO 6165 - machine types and definitions
• ISO 3744 - general sound power determination (reference engineering method)
• ISO 6393 / ISO 6394 / ISO 6396 - complementary test codes (stationary conditions and operator position)
• ISO 9249 - engine test code; IEC 61672-1 - sound level meter specifications

Keywords: ISO 6395:2008, earth-moving machinery, sound power level, A-weighted, dynamic test conditions, noise emitted, test site, measurement hemisphere, LWA.