ISO 10140-3:2021

Overview

ISO 10140-3:2021 - Acoustics: Laboratory measurement of sound insulation of building elements - Part 3: Measurement of impact sound insulation - specifies laboratory methods to measure the impact sound insulation of floor assemblies. The standard defines test arrangements, measurement procedures and evaluation rules used to compare floor constructions, classify products by acoustic performance, support product design and estimate in‑situ behaviour (with caveats). Measurements are carried out in dedicated laboratory facilities where flanking transmission is suppressed.

Key topics and technical requirements

• Test configuration: Two vertically adjacent rooms (source room above, receiving room below) separated by the floor under test.
• Impact sources: Standard tapping machine (see ISO 10140-5:2021, Annex E) to simulate footsteps wearing shoes. Alternative methods include a modified tapping machine or a heavy/soft impact source (Annex A / ISO 10140-5 Annex F) to simulate strong low‑frequency impacts (bare feet, children jumping).
• Measured quantities: Impact sound pressure levels (Li) and normalized impact sound pressure level (Ln) - Ln = Li + 10·log10(A/A0) where A is the measured equivalent absorption area of the receiving room and A0 = 10 m2.
• Frequency range: Measurements typically cover one‑third octave bands with centre frequencies from 100 Hz to 5 000 Hz (optionally down to 50 Hz).
• Data processing: Sound pressure levels in the receiving room plus reverberation time measurements are used to compute equivalent absorption area and normalized results. Procedures for correction of airborne transmission, uncertainty estimation and expression of results are defined.
• Laboratory and equipment requirements: Facilities and equipment must comply with ISO 10140-5. Calibration and measurement equipment follow referenced IEC standards (e.g., IEC 60942, IEC 61672‑1, IEC 61260‑1).
• Scope limits: Results apply to laboratory conditions only; direct field application requires accounting for flanking paths, boundary conditions and loss factor.

Applications and users

ISO 10140-3:2021 is used to:

• Compare and classify floor constructions and floor coverings by impact sound performance.
• Support acoustic product design (floor systems, underlays, resilient layers).
• Provide laboratory data for estimating in‑situ building performance when combined with field factors.
• Provide test protocols for accredited acoustics laboratories.

Typical users:

• Acoustic consultants and test laboratories
• Flooring and building product manufacturers
• Architects, structural and building services engineers
• Regulatory bodies and compliance assessors

Related standards

• ISO 10140-1, -2, -4, -5 (other parts of the laboratory measurement series)
• ISO 717-2 (rating of impact sound insulation)
• ISO 12999-1 (measurement uncertainties in building acoustics)
• IEC 60942, IEC 61672‑1, IEC 61260‑1 (electroacoustics and calibration)

Keywords: ISO 10140-3:2021, impact sound insulation, tapping machine, laboratory measurement, normalized impact sound pressure level, floor assemblies, reverberation time, flanking transmission.