🏗️ Laboratory measurement of airborne sound insulation of building elements (walls, floors, doors, windows, façades, glazing, small technical elements) — sound reduction index R from levels in two rooms and the absorption of the receiving room, level difference Dn,e, one-third-octave bands 100–5 000 Hz, PN-EN ISO 10140-2

Construction PN-EN ISO 10140-2

Overview

WHAT THE STANDARD COVERS. Scope from the PKN catalogue card of PN-EN ISO 10140-2:2021-10 (Polish version), in full (our translation): “This document specifies a laboratory method for measuring the airborne sound insulation of building products such as walls, floors, doors, windows, shutters, façade elements, façades, glazing, small technical elements such as air transfer devices, ventilation grilles, outdoor air inlets, electrical ducts, sealing systems and various combinations, e.g. walls and floors with linings, suspended ceilings or raised floors. The test results can be used to compare the sound insulation properties of building elements, to classify elements according to their sound insulation capabilities, to support the design of building products requiring certain acoustic properties and to estimate the in situ performance in completed buildings. The measurements are performed in laboratory test facilities in which sound transmission via flanking paths is suppressed. Results of measurements made in accordance with this document are not directly applicable to the field situation without accounting for other factors affecting sound insulation, such as flanking transmission, boundary conditions and total loss factor”. We read the text in the sample of ISO 10140-2:2021 in the French version (we did not find an English sample of the 2021 edition) from the cover to the introduction of Clause 6 (types of test elements a)–e) and ambient conditions), and for comparison the English sample of the previous edition ISO 10140-2:2010; we do not have the rest of Clause 6 (mounting in the large and small opening), Clauses 7–8 or the annexes.

ACCORDING TO THE TEXT OF ISO 10140-2:2021 (foreword, introduction, Clauses 1–6, introduction). The standard was prepared by ISO/TC 43 “Acoustics”, SC 2 “Building acoustics”, together with CEN/TC 126; the second edition replaces ISO 10140-2:2010. Changes: references updated (Clause 2 and in the text), terms and definitions updated (Clause 3), title of Clause 8 changed to “Measurement uncertainty”. Introduction and Table 1 as in Part 1: Part 2 gives the procedure for measuring airborne sound insulation according to Parts 4 and 5; for products with specific rules the measurement is made according to Part 1. References (2): ISO 717-1, ISO 10140-1, ISO 10140-4, ISO 10140-5, ISO 12999-1. Terms (3): sound reduction index R = 10 lg(W₁/W₂) — ten times the logarithm of the ratio of the sound power incident on the element to the power radiated by it; in the laboratory R = L₁ − L₂ + 10 lg(S/A), where L₁ and L₂ — energy-average sound pressure levels in the source and receiving rooms, S — area of the test opening, A — equivalent absorption area of the receiving room (the formula assumes diffuse fields and transmission only through the element; in English-speaking countries the term “transmission loss” is also used); apparent sound reduction index R′ = 10 lg(W₁/(W₂ + W₃)), when the power W₃ transmitted by flanking elements is significant (in practice calculated with the same formula from levels); element-normalized level difference Dn,e = L₁ − L₂ + 10 lg(A₀/A), with A₀ = 10 m² in the laboratory, and for n identical elements measured together — 10 lg(nA₀/A); small technical element — a building element other than windows and doors, with an area of less than 1 m², transmitting sound between rooms or to the outside independently of adjacent elements. Facility and equipment (4): according to ISO 10140-5 (rooms, sound sources, level measuring equipment and its calibration). Procedure (5.1): two adjacent rooms (horizontally or vertically), the element in the opening of the wall separating them; in the source room a diffuse field from a moving loudspeaker or from at least two fixed positions; average levels in both rooms, normally in one-third-octave bands with centre frequencies 100–5 000 Hz (optionally from 50 Hz); absorption of the receiving room from the reverberation time; procedures for averaging, background noise correction and reverberation time measurement — in ISO 10140-4; nobody may be present in either room during the measurement; for systems improving insulation (linings, independent leaves) the procedure is repeated for the basic element and with the lining. Field in the source room (5.2): qualification of loudspeakers, number and positions according to ISO 10140-5; with a single source in two or more positions, the measurement may also be repeated in the opposite direction by exchanging the rooms — but not when one side of the element is significantly more absorbent; microphones outside the direct field of the source. Calculation (5.3): R or Dn,e from levels (corrected for background) and reverberation time according to ISO 10140-4; octave values from three one-third-octave values: R_oct = −10 lg[(1/3) Σ 10^(−R_third/10)] (likewise Dn,e); final result to not more than 0,1 dB; single-number rating according to ISO 717-1. Results (5.4): R or Dn,e in decibels for all one-third-octave bands, to one decimal place, in a table and graph: 5 mm per one-third octave and 20 mm per 10 dB, recommended form in Annex B. Test element (6, introduction): a) fills the whole large opening (e.g. masonry, timber floor) — according to 6.2; b) of the same type but smaller — according to 6.3; c) of fixed dimensions smaller than the opening (doors, windows, panes, panels) — according to 6.4; d) small, with poorly defined dimensions (air transfer devices, air inlets) — according to 6.5; e) connected to a basic element (lining, floating floor, window frame, sealing) — according to the specific rules of Part 1; sound transmission may depend on temperature, relative humidity and static pressure during the test and conditioning — the conditions shall be recorded. Comparison with the 2010 edition (English sample, Clauses 3 and 5): the same formulae (1)–(6) for R, R′ and Dn,e with A₀ = 10 m², the same range 100–5 000 Hz (optionally from 50 Hz), precision 0,1 dB and graph scale; according to the 2021 foreword, the changes concern references, definitions and the name of Clause 8.

STATUS (PKN catalogue cards as of 02.10.2026). The card of PN-EN ISO 10140-2:2021-10 (Polish version, published 05-02-2025, 24 pages, price group M) has no “Withdrawn” header: Sector of Construction and Building Structures, KT 253 Architectural Acoustics, ICS 91.120.20, “Introduces: EN ISO 10140-2:2021 [IDT], ISO 10140-2:2021 [IDT]”, “Replaces: PN-EN ISO 10140-2:2011” (German, English and Polish versions). The card of PN-EN ISO 10140-2:2011 (Polish version) has the “Withdrawn” header: withdrawal date 18-10-2021, “Replaced by: PN-EN ISO 10140-2:2021-10” (English and Polish versions); it itself replaced the former standards of the PN-EN ISO 140 and PN-EN 20140 series (among others Parts 1, 3, 6, 8, 10, 11 and 16). The PKN search engine (query “PN-EN ISO 10140-2”, 02.10.2026) shows the 2011 (versions d, e, p) and 2021-10 (e, p) editions. According to the EVS catalogue, ISO 10140-2:2021 is valid from 15.04.2021, previously ISO 10140-2:2010. What changed for the result: according to the foreword — references, definitions and the name of the uncertainty clause; the formulae for R and Dn,e are the same in both editions.

HOW MANY LABORATORIES AND IN WHAT FORM (copy of the accreditation scope database, data up to 17.09.2026, read 02.10.2026). The number 10140-2 appears in 16 records of 6 laboratories: AB 023, AB 054, AB 818, AB 1054, AB 1241, AB 1271. In the current scopes on the PCA website (read 02.10.2026, issues from 16.07.2025 to 28.07.2026) AB 818 and AB 1271 cite the 2021-10 edition, AB 023, AB 054, AB 1054 and AB 1241 — the designation alone without a date. In 14 of 16 records PN-EN ISO 10140-1 stands next to it (exception: two records of AB 023, which cites 10140-2 with Part 3 or with the former PN-EN ISO 140-10). The “Laboratories” tab (“PN-EN ISO 10140-2”) shows the same 6 laboratories — checked with a query of the tab on the labcoda.pl production server on 02.10.2026.

WHAT THE LABORATORIES TEST (PCA entries). “Airborne sound insulation of building elements” in the frequency range (100–5 000) Hz (AB 023: with the possibility of measuring from 50 Hz; partitions, doors, industrial and garage doors, ventilation elements and other objects with an area below 1 m²), internal walls, doors, panes, windows, shutters, ship panels and bulkheads (AB 1241), “Sound reduction index R in 1/3-octave bands”, “Improvement of the sound reduction index ΔR” of linings and “Element-normalized level difference Dn,e” of ventilation elements (AB 1271).

WHERE A SEEMINGLY CORRECT RESULT IS EASY TO GET. With flanking transmission: the laboratory result R does not transfer directly to the building — in the field flanking transmission, boundary conditions and the loss factor are added (scope); in a laboratory with insufficiently suppressed flanking transmission one actually measures R′. With the direction of measurement: exchanging source and receiving rooms is not allowed when one side of the element is significantly more absorbent (5.2). During measurement: a person in the room changes the sound field (5.1); microphones in the direct field of the source raise L₁. With octave bands: octave values are calculated on an energy basis from three one-third octaves, not as an arithmetic mean (5.3). With small elements: for air vents and transfer elements the quantity is Dn,e (with A₀ = 10 m²), not R — R calculated from the opening area is meaningless for an element of undefined area (3.3, 3.4). With conditions: temperature, humidity and static pressure affect the result and must be recorded (6).

WHAT WE DO NOT GIVE. We do not have Clauses 6.1–6.5 (mounting in the large and small opening, boundary requirements, conditioning), 7 (report), 8 (measurement uncertainty) or the annexes (among others form B) — so we give no mounting requirements, report content or uncertainty values; the procedures for background correction and reverberation time measurement are in ISO 10140-4, which we have not read.

Method principle

In the source room a loudspeaker generates a diffuse sound field; average sound pressure levels L₁ and L₂ on both sides of the test element are measured in one-third-octave bands, as well as the reverberation time in the receiving room (equivalent absorption area A); sound reduction index R = L₁ − L₂ + 10 lg(S/A), for small technical elements Dn,e = L₁ − L₂ + 10 lg(A₀/A) with A₀ = 10 m²; single-number rating according to ISO 717-1.

Applications

• Walls, floors, doors, gates, windows, shutters, façades and glazing — laboratory airborne sound insulation; 6 laboratories in PCA scopes
• Small technical elements — air vents, grilles, air inlets, transfer elements, seals (Dn,e)
• Linings, independent leaves, suspended ceilings — improvement of insulation ΔR (measurement with and without the basic element)

Key parameters

Standard

Standard number

PN-EN ISO 10140-2:2021-10 (wersja polska; EN ISO 10140-2:2021 IDT, ISO 10140-2:2021 IDT)

Title (PL)

Akustyka — Pomiar laboratoryjny izolacyjności akustycznej elementów budowlanych — Część 2: Pomiar izolacyjności od dźwięków powietrznych

Title (EN)

Acoustics — Laboratory measurement of sound insulation of building elements — Part 2: Measurement of airborne sound insulation

Step-by-step procedure

1. Element and mounting

   Establish the element type a)–e) and mount it according to Clause 6 and the specific rules of Part 1. PN-EN ISO 10140-2:2021-10 current (PKN cards as of 02.10.2026).

2. Field in the source room

   Moving loudspeaker or at least two fixed positions; microphones outside the direct field; nobody in the rooms.

3. Measurement of levels and reverberation

   Average levels L₁ and L₂ in one-third-octave bands 100–5 000 Hz (optionally from 50 Hz), background correction and reverberation time according to ISO 10140-4.

4. Calculation

   R = L₁ − L₂ + 10 lg(S/A) or Dn,e = L₁ − L₂ + 10 lg(A₀/A); octaves on an energy basis from three one-third octaves; result to 0,1 dB.

5. Results and report

   Table and graph (5 mm per one-third octave, 20 mm per 10 dB), single-number rating according to ISO 717-1; record temperature, humidity and static pressure.

Required equipment and apparatus

Health and safety (OHS)

• The standard contains no safety warnings in the part we read; high sound levels in the source room — nobody stays in the rooms during measurement (5.1)
• TECHNICAL NOTE: the laboratory result R is not applied directly in a building without assessing flanking transmission

Frequently asked questions