ISO 11546-2:1995 PDF

ISO 11546-2:1995 - Acoustics: Determination of sound insulation performances of enclosures - Part 2: Measurements in situ (for acceptance and verification purposes) Organization: ISO

Overview

ISO 11546-2:1995 specifies in situ (on-site) measurement methods for determining the sound insulation performance (insertion loss) of total machine enclosures. It is intended for acceptance and verification of enclosures as installed and applies to whole enclosures (not individual panels). The standard describes procedures using either the actual sound source (the machine) or an artificial sound source, and gives guidance on instrumentation, test environments, uncertainty and reporting.

Keywords: ISO 11546-2, acoustics, sound insulation, in situ measurements, machine enclosures, insertion loss

Key topics and technical requirements

• Scope and applicability
  • Applies only to total enclosures (not individual doors, panels or silencers).
  • Measurement results depend on installation and workmanship.
• Measurement quantities
  • Sound power insulation (Dw), A-weighted sound power insulation (DwA), sound pressure insulation (Dp), and A-weighted equivalents (DpA).
  • Single-number weighted indices (reference to ISO 717-1 method with Dw substituted as required).
• Measurement methods
  • Methods using the actual sound source when practicable.
  • Artificial sound source methods when the machine cannot operate or identical conditions cannot be ensured.
  • Survey and engineering methods for sound power or sound pressure depending on environment (e.g., hard-walled test room, outdoors, reverberant field).
• Instrumentation and calibration
  • Use of class/type 1 sound level meters and filters for octave/one‑third-octave measurements; integrating-averaging meters recommended.
  • Pre- and post-measurement calibration using an acoustic calibrator (type 1, ±0.3 dB).
• Practical measurement considerations
  • Leak ratio and fill ratio definitions; recommended low leak ratio (ideally