ISO/TC 43 - Acoustics

1.1 General This document specifies methods for determining the sound power level of a noise source from sound pressure levels measured on a surface enveloping the noise source (machinery or equipment) in an environment that approximates to an acoustic free field near one or more reflecting planes. The sound power level produced by the noise source, in frequency bands or with A-weighting applied, is calculated using those measurements. NOTE Differently shaped measurement surfaces can yield differing estimates of the sound power level of a given noise source which are accounted for in the uncertainty associated with this test method. An appropriately drafted noise test code (see ISO 12001) gives detailed information on the selection of the surface. 1.2 Types of noise and noise sources The methods specified in this document are suitable for all types of noise (steady, non-steady, and fluctuating) as defined in ISO 12001, except for short duration, impulsive events. This document is applicable to all types and sizes of noise source (e.g. stationary or slowly moving component or sub-assembly), provided that the conditions for the measurements can be met. NOTE It is possible that the conditions for measurements given in this document are impracticable for very tall or very long sources such as chimneys, ducts, conveyors and multi-source industrial plants. A noise test code for the determination of noise emission of specific sources can provide alternative methods in such cases. 1.3 Test environment The test environments that are applicable for measurements made in accordance with this document can be located indoors or outdoors, with one or more sound-reflecting planes present on or near which the noise source under test is mounted. The ideal environment is a completely open space with no bounding or reflecting surfaces other than the reflecting plane(s), such as that provided by a qualified hemi-anechoic chamber, but procedures are given for applying corrections (within limits that are specified) in the case of environments that are less than ideal. Annex A or ISO 26101-2 specifies methods for determining the adequacy of the test environment and for determination of corrections to be applied to account for the effect of the test environment. 1.4 Measurement uncertainty Information is given on the uncertainty of the sound power levels determined in accordance with this document, for measurements made in limited bands of frequency and with frequency A-weighting applied. Annex I specifies procedures for testing laboratories that can be used to reduce measurement uncertainty. The uncertainty conforms to ISO 12001, accuracy grade 2 (engineering grade). General information on measurement uncertainty is provided in this document and additional information can be found in ISO 5114-1[8].

This document defines the procedures for noise control of primarily open plants and the requirements on equipment suppliers for reporting and testing of noise. It is applicable to the following: — specification of procedures for noise control during engineering of a new plant and modification/extension of existing plants (construction and commissioning noise procedures are outside the scope of this document); — definition of responsibilities of parties involved, viz. “end-user”, “engineering contractor” and “equipment supplier”; — description of general procedures to arrive at noise requirements for individual equipment, based on overall noise requirements for the plant. Input to purchase specifications is presented in REF Annex_sec_A \r \h Annex A. A schematic flowchart, reviewing the noise control process, is presented in REF Annex_sec_B \r \h Annex B 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000C00000041006E006E00650078005F007300650063005F0042000000 and a summary of action items is presented in REF Annex_sec_C \r \h Annex C 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000C00000041006E006E00650078005F007300650063005F0043000000 . An example of an equipment noise data sheet is presented in REF Annex_sec_E \r \h Annex E 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000C00000041006E006E00650078005F007300650063005F0045000000 .

This document specifies measurement methods and conditions to obtain reproducible and comparable exterior noise emission levels and spectra for all kinds of vehicles operating on rails or other types of fixed track, hereinafter conventionally called “unit”. This document is applicable to type testing of units. It provides measurement procedures for vehicle exterior noise (in general, a vehicle type test is carried out using only a selected subset of these tests): — when the vehicle is moving at constant speed; — when the vehicle is accelerating or decelerating; — when the vehicle is stationary in different operating conditions. It does not include all the instructions to characterize the noise emission of the infrastructure related sources (bridges, crossings, switching, impact noise, curving noise, etc.). This document does not apply to — the noise emission of track maintenance units while working, — environmental impact assessment (collection of data to be used in a prediction method for environmental assessment), — noise immission assessment, — guided buses, and — warning signal noise. The results can be used, for example — to characterize the exterior noise emitted by units, — to compare the noise emission of various units on a particular track section, and — to collect basic source data for units. NOTE Additional guidance is provided in Annex E for measurements in the specific case of urban rail vehicles.

ISO 17208 series describe procedures for the measurement of underwater sound radiated by the ship under test, and for calculating sound source quantities such as source level and radiated noise level from the measurement results. In ISO 17208-1 to ISO 17208-3 it is presumed that the ship under test cooperates in the measurements, sailing multiple runs over a specified track past the measurement system at a specified speed with pre-determined machinery configurations. Opportunistic measurements of the radiated sound of passing ships are outside the scope of these three standards. Part 1 of the ISO 17208 standards[ REF Reference_ref_4 \r \h 1 08D0C9EA79F9BACE118C8200AA004BA90B0200000008000000100000005200650066006500720065006E00630065005F007200650066005F0034000000 ] provides the procedure to quantify the underwater sound from the ship in terms of its radiated noise level, which is calculated from the sound pressure level (SPL) measured in the far field of the ship, in beam aspect, scaled by the distance to CPA and reported in decidecade bands. The intended use of radiated noise level is to show compliance with contract requirements or criteria, for comparison of one ship to another ship, to enable periodic signature assessments, and for research and development. ISO 17208-2[ REF Reference_ref_4 \r \h 1 08D0C9EA79F9BACE118C8200AA004BA90B0200000008000000100000005200650066006500720065006E00630065005F007200650066005F0034000000 ] specifies methods for calculating the source level of an equivalent monopole source at a specified nominal source depth from the radiated noise level values obtained according to ISO 17208-1. The intended use of source level, with associated nominal source depth, is to perform far field sound predictions such as needed for environmental impact studies or for creating underwater sound contour maps. ISO 17208-1 and ISO 17208-2[ REF Reference_ref_4 \r \h 1 08D0C9EA79F9BACE118C8200AA004BA90B0200000008000000100000005200650066006500720065006E00630065005F007200650066005F0034000000 ] are applicable for measurements in deep water, defined as water depth greater than the larger of 150 m and 1,5 times overall ship length. The allowable water depths and environmental conditions for part 3 measurements are described in REF Section_sec_4.5 \r \h 4.5 08D0C9EA79F9BACE118C8200AA004BA90B020000000800000010000000530065006300740069006F006E005F007300650063005F0034002E0035000000 . This document specifies procedures for the measurement of underwater sound radiated by the ship under test in shallow water. It also specifies procedures for the calculation of source level, with associated nominal source depth, from the sound pressure measurements, accounting for the relevant phenomena that govern the propagation of sound in shallow water. These calculations are described in REF Section_sec_7 \r \h Clause 7 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000E000000530065006300740069006F006E005F007300650063005F0037000000 . Once the source level has been calculated, other metrics may be calculated from the source level and the source depth. REF Section_sec_7.3 \r \h 7.3 08D0C9EA79F9BACE118C8200AA004BA90B020000000800000010000000530065006300740069006F006E005F007300650063005F0037002E0033000000 provides a procedure for calculating the radiated noise level that would have been measured in deep water according to ISO 17208-1 for the same ship with the same operating condition.

This document provides requirements and recommendations for measuring and reporting ambient sound in water, as characterized by sound pressure and selected quantities that can be derived from sound pressure. “Ambient sound” implies sound from any source except sources of self-noise. The scope includes equipment performance, calibration and deployment, digital data acquisition and data processing. Data processing is the process of converting raw data into a form and context necessary to be interpreted by people and computers. The scope includes data analysis and reporting of recordings of duration one day or longer. Five data processing stages are considered: raw digital acquisition data3), sound pressure time series, sound pressure level time series, sound pressure spectra and their statistics. The scope excludes measurement of particle motion. 3)The word data is generally used as a collective noun in this document; the plural form is reserved for cases where the constructive relationship to individual observations or measurements is to be emphasized.

This document specifies computational methods for determining the acoustical source level of projectile sound and its one-third octave band spectrum, expressed as the sound exposure level for nominal mid-band frequencies from 12,5 Hz to 10 kHz. It also specifies a method on how to use this source level to calculate the sound exposure level at a receiver position. Results obtained with this document can be used as a basis for assessment of projectile sound from shooting ranges. Additionally, the data can be used to determine sound emission or immission from different types of ammunition and weapons. The prediction methods are applicable to outdoor conditions and straight projectile trajectories. Two computational methods are given to determine the acoustical source level: one for streamlined projectile shapes and one for non-streamlined shapes, such as pellets.

This document specifies a computational method (in line with ISO 17201-4) for estimating the acoustic source data of muzzle blast and explosions on the basis of non-acoustic data for firearms with calibres less than 20 mm and explosions less than 50 g TNT equivalent. This document addresses those cases where no source measurements exist. This document can also be used as an interpolation method between measurements of muzzle blast. Source data are given in terms of spectral angular source energy covering the frequency range from 12,5 Hz to 10 kHz and can be used as data input for sound propagation calculation. This document does not apply to the prediction of sound levels for the assessment of hearing damage; nor can it be used to predict sound pressure levels or sound exposure levels at distances where linear acoustics do not apply.

This document specifies a method for measuring workers’ exposure to noise in a working environment and calculating the noise exposure level. This document deals with A-weighted levels but is applicable also to C-weighted levels. Three different strategies for measurement are specified. The method is applicable for detailed noise exposure studies or epidemiological studies of hearing damage or other adverse effects. The measuring process requires observation and analysis of the noise exposure conditions so that the quality of the measurements can be controlled. This document provides methods for estimating the uncertainty of the results. This document is not intended for assessment of masking of oral communication or assessment of infrasound, ultrasound and non-auditory effects of noise. It does not apply to the measurement of the noise exposure of the ear when hearing protectors are worn. Results of the measurements performed in accordance with this document can provide useful information when defining priorities for noise control measures.

This document specifies a test method for measuring in situ the sound absorption coefficient of road surfaces for the one-third octave band frequencies ranging from 250 Hz to 1 600 Hz under normal incidence conditions. If necessary for practical applications the diameter of the tube can be reduced to 80 mm. This will increase the upper boundary of the frequency range to 2 000 Hz one-third octave band (see REF Section_sec_5.4 \r \h 5.4 08D0C9EA79F9BACE118C8200AA004BA90B020000000800000010000000530065006300740069006F006E005F007300650063005F0035002E0034000000 ) but reduces the area under test. The test method is intended for the following applications: — determination of the sound absorption coefficient (and, if of interest, also the complex acoustical impedance) of semi-dense to dense road surfaces; — determination of the sound absorption properties of test tracks according to ISO 10844[ REF Reference_ref_4 \r \h 2 08D0C9EA79F9BACE118C8200AA004BA90B0200000008000000100000005200650066006500720065006E00630065005F007200650066005F0034000000 ] or other similar standards and test surfaces defined in national and international type approval regulations for road vehicles and their tyres; — verification of the compliance of the sound absorption coefficient of a road surface with design-specifications or other requirements.

This document provides requirements and supporting information on analysis of data collected in situ through methods as specified in ISO/TS 12913-2.

This document provides a definition, a conceptual framework and a categorisation framework for non-acoustic factors (sometimes also referred to as “contextual factors”). It identifies and lists attributes relevant to the measurements, reporting and assessment of self-reported health outcomes attributable to noise and soundscape studies, as well as for the planning, design and management of soundscape and noise interventions.

This document specifies a procedure for determining the magnitude of pavement surface megatexture by measuring the surface profile and calculating a megatexture descriptor from this profile. The technique is designed to give meaningful and accurate measurements and descriptions of pavement megatexture for various purposes, such as for the prediction of the acoustic quality of the pavement or the assessment of the rolling resistance. Since there is an overlap between megatexture and the surrounding ranges, megatexture descriptors unavoidably have a certain correlation with corresponding measures in those ranges. This document specifies measurements and procedures which are in relevant parts compatible with those in ISO 13473-1[4], ISO 8608[6] and EN 13036-5[7].

This document is derived from ISO 362-1[2] and specifies an engineering method for measuring the sound emitted by M and N category road vehicles at standstill and low speed operating conditions. The specifications reproduce the level of sound which is generated by the principal vehicle sound sources consistent with stationary and low speed vehicle operating conditions relevant for pedestrian safety. The method is designed to meet the requirements of simplicity as far as they are consistent with reproducibility of results under the operating conditions of the vehicle. The test method requires an acoustic environment which is only obtained in an extensive open space. Such conditions usually exist during the following: — measurements of vehicles for regulatory certification; — measurements at the manufacturing stage; — measurements at official testing stations. The results obtained by this method give an objective measure of the sound emitted under the specified conditions of test. It is necessary to consider the fact that the subjective appraisal of the annoyance, perceptibility, and/or detectability of different motor vehicles or classes of motor vehicles due to their sound emission are not simply related to the indications of a sound measurement system. As annoyance, perceptibility and/or detectability are strongly related to personal human perception, physiological human condition, culture, and environmental conditions, there are large variations and therefore these terms are not useful as parameters to describe a specific vehicle condition. Spot checks of vehicles chosen at random rarely occur in an ideal acoustic environment. If measurements are carried out on the road in an acoustic environment which does not fulfil the requirements stated in this document, the results obtained might deviate appreciably from the results obtained using the specified conditions. In addition, this document provides an engineering method to measure the performance of external sound generation systems intended for the purpose of providing acoustic information to pedestrians on a vehicle’s operating condition. This information is reported as objective criteria related to the external sound generation system’s sound pressure level, frequency content, and changes in sound pressure level and frequency content as a function of vehicle speed. This document adds a metric related to the human perception of tonal loudness, the psychoacoustic tonality. The psychoacoustic tonality can be used to estimate audible frequency shifts of the sounds by identifying the most audible component in each auditory frequency band (critical band), as well as to determine if the band(s) so identified meet audibility criteria. Annex A and Annex C contains background information relevant in the development of this document.

This document specifies two procedures for the in situ determination of the insertion loss of underwater noise abatement measures (noise abatement systems). The impulsive sound of pile driving is used as the sound source for the investigation of noise abatement systems. This document does not apply to artificial sound sources and investigations under laboratory conditions. Apart from the correct application of the respective noise abatement system, the achieved sound attenuation also depends on the installation conditions (e.g. type of hammer, driving energy, pile dimensioning) as well as on the environmental conditions (e.g. water depth, seafloor classification and bathymetry, current and wind conditions) and the flanking transmission via the seafloor.

This document gives guidance on the determination of measurement uncertainties of sound power levels determined according to ISO 3741, ISO 3743-1, ISO 3743-2, ISO 3744, ISO 3745, ISO 3746, ISO 3747 or according to a noise test code based on one of these measurement standards.

This document specifies methods for qualifying an environment that approximates to an acoustic free field near one or more reflecting planes. The goal of the qualification is to determine the environmental correction K2 , which is used to correct for reflected sound when determining the sound power level or sound energy level of a noise source from sound pressure levels measured on a surface enveloping the noise source (machinery or equipment) in such an environment. In practice, the K2 value determined will be a function of both the reflected sound from the test environment and the shape and size of the measurement surface used for the K2 determination. For the purposes of this document and the documents that refer to it, the differences between K2 values determined with different measurement surfaces are assumed to be included in the stated measurement uncertainty for the test method.

This document is a supplement to ISO 21388 which applies to hearing aid fitting management (HAFM) services offered by hearing aid professionals (HAP). It focusses on tele-services which can substitute, or complement services defined in ISO 21388, and it defines services which is provided in the facilities of the HAP. Moreover, this document specifies important preconditions such as education, facilities and systems that are required to ensure proper tele-services. If not other stated all definitions and requirements of ISO 21388 also apply for this document without further notice. Furthermore, it is tried to keep the structure of ISO 21388 to make it easier to use both standards together. It is recognized that certain populations with hearing loss such as children, persons with other disabilities or persons with implantable devices can require services outside the scope of this document. Assisted tele-services provided by non-hearing aid professionals, self-fitting, and other non-hearing care related services are also outside the scope of this document.

This document describes the methods that are available to perform a spectral analysis of a pavement surface profile. It specifies a method for performing spatial frequency analysis (or texture wavelength analysis) of two-dimensional surface profiles that describe the pavement texture amplitude as a function of the distance along a straight or curved trajectory over the pavement. It also details an alternative (non-preferred) method to obtain these spectra: a) constant-percentage bandwidth obtained by digital filtering (normative method); b) constant narrow bandwidth frequency analysis by means of discrete Fourier transform (DFT), followed by a transformation of the narrow-band spectrum to an octave- or one-third-octave-band spectrum (informative). The result of the frequency analysis will be a spatial frequency (or texture wavelength) spectrum in constant-percentage bandwidth bands of octave or one-third-octave bandwidth. The objective of this document is to standardize the spectral characterization of pavement surface profiles. This objective is pursued by providing a detailed description of the analysis methods and related requirements for those who are involved in pavement characterization but are not familiar with general principles of frequency analysis of random signals. These methods and requirements are generally applicable to all types of random signals; however, they are elaborated in this document for their use in pavement surface profile analysis. NOTE The spectral analysis as specified in this document cannot express all characteristics of the surface profile under study. In particular, the effects of asymmetry of the profile, e.g. the difference of certain functional qualities for “positive” and “negative” profiles cannot be expressed by the power spectral density, as it disregards any asymmetry of the signal (see Annex B).

This document specifies an engineering method for the measurement of sound pressure levels in rooms from service equipment installed in the building. This document covers specifically measurements of sound from sanitary installations, mechanical ventilation, heating and cooling service equipment, lifts, rubbish chutes, heating devices, blowers, pumps and other auxiliary service equipment, and motor driven car park doors. It can also be applied to measurements of sounds from other types of equipment or activities within the building, e.g. noise from sport facilities or restaurants. The measurement of noise from external sound sources generating air-borne or ground-borne noise in the building are not included in this document. The methods are suitable for rooms with volumes of approximately 300 m3 or less for instance, in dwellings, hotels, schools, offices and hospitals. The methods are not intended for measurements in large auditoria or concert halls.

This document specifies methods for measuring the airborne noise emitted by small air-moving devices (AMDs), such as those used for cooling electronic, electrical, and mechanical equipment where the sound power level of the AMD is of interest. Examples of these AMDs include propeller fans, tube-axial fans, vane-axial fans, centrifugal fans, motorized impellers, and their variations. This document describes the test apparatus and methods for determining the airborne noise emitted by small AMDs as a function of the volume flow rate and the fan static pressure developed by the AMD on the test apparatus. It is intended for use by AMD manufacturers, by manufacturers who use AMDs for cooling electronic equipment and similar applications, and by testing laboratories. It provides a method for AMD manufacturers, equipment manufacturers and testing laboratories to obtain comparable results. Results of measurements made in accordance with this document are expected to be used for engineering information and performance verification, and the methods can be cited in purchase specifications and contracts between buyers and sellers. The ultimate purpose of the measurements is to provide data to assist the designers of electronic, electrical or mechanical equipment which contains one or more AMDs. Based on experimental data, a method is given for calculating the maximum volume flow rate of the scaled plenum up to which this document is applicable.

This document specifies an engineering method for calculating the attenuation of sound during propagation outdoors in order to predict the levels of environmental noise at a distance from a variety of sources. The method predicts the equivalent continuous A-weighted sound pressure level (as described in ISO 1996-series) under meteorological conditions favourable to propagation from sources of known sound emission. These conditions are for downwind propagation or, equivalently, propagation under a well-developed moderate ground‑based temperature inversion, such as commonly occurs in clear, calm nights. Inversion conditions over extended water surfaces are not covered and may result in higher sound pressure levels than predicted from this document (see e.g. References [11] and [12]). The method also predicts a long-term average A‑weighted sound pressure level as specified in ISO 1996-1 and ISO 1996-2. The long-term average A‑weighted sound pressure level encompasses levels for a wide variety of meteorological conditions. Guidance has been provided to derive a meteorological correction based on the angular wind distribution relevant for the reference or long-term time interval as specified in ISO 1996-1:2016, 3.2.1 and 3.2.2. Examples for reference time intervals are day, night, or the hour of the night with the largest value of the sound pressure level. Long-term time intervals over which the sound of a series of reference time intervals is averaged or assessed representing a significant fraction of a year (e.g. 3 months, 6 months or 1 year). The method specified in this document consists specifically of octave band algorithms (with nominal mid-band frequencies from 63 Hz to 8 kHz) for calculating the attenuation of sound which originates from a point sound source, or an assembly of point sources. The source (or sources) may be moving or stationary. Specific terms are provided in the algorithms for the following physical effects: — geometrical divergence; — atmospheric absorption; — ground effect; — reflection from surfaces; — screening by obstacles. Additional information concerning propagation through foliage, industrial sites and housing is given in Annex A. The directivity of chimney-stacks to support the sound predictions for industrial sites has been included with Annex B. An example how the far-distance meteorological correction C0 can be determined from the local wind-climatology is given in Annex C. Experiences of the last decades how to predict the sound pressure levels caused by wind turbines is summarized in Annex D. The method is applicable in practice to a great variety of noise sources and environments. It is applicable, directly, or indirectly, to most situations concerning road or rail traffic, industrial noise sources, construction activities, and many other ground-based noise sources. It does not apply to sound from aircraft in flight, or to blast waves from mining, military, or similar operations. To apply the method of this document, several parameters need to be known with respect to the geometry of the source and of the environment, the ground surface characteristics, and the source strength in terms of octave band sound power levels for directions relevant to the propagation. If only A‑weighted sound power levels of the sources are known, the attenuation terms for 500 Hz may be used to estimate the resulting attenuation. The accuracy of the method and the limitations to its use in practice are described in Clause 9.

This document defines the acoustic performance of four classes (Classes A, B, C and D) of pipe insulation. It also defines a standardized test method for measuring the acoustic performance of any type of material system construction, thereby allowing existing and new insulation constructions to be rated against the four classes. Furthermore, this document presents some typical types of construction that would be expected to meet these acoustic performance classes. This document is applicable to the acoustic insulation of cylindrical steel pipes and to their piping components. It is valid for pipes up to 1 m in diameter and a minimum wall thickness of 4,2 mm for diameters below 300 mm, and 6,3 mm for diameters from 300 mm and above. It is not applicable to the acoustic insulation of rectangular ducting and vessels or machinery. This document covers both design and installation aspects of acoustic insulation and provides guidance to assist noise control engineers in determining the required class and extent of insulation needed for a particular application. It gives typical examples of construction methods, but the examples are for information only and not meant to be prescriptive. This document emphasises the aspects of acoustic insulation that are different from those of thermal insulation, serving to guide both the installer and the noise control engineer. Details of thermal insulation are beyond the scope of this document.

This test method covers the use of an impedance tube, two microphone locations and a frequency analysis system for the determination of the sound absorption coefficient of sound absorbing materials for normal incidence sound incidence. It can also be applied for the determination of the acoustical surface impedance or surface admittance of sound absorbing materials. As an extension, it can also be used to assess intrinsic properties of homogeneous acoustical materials such as their characteristic impedance, characteristic wavenumber, dynamic mass density and dynamic bulk modulus. The test method is similar to the test method specified in ISO 10534-1 in that it uses an impedance tube with a sound source connected to one end and the test sample mounted in the tube at the other end. However, the measurement technique is different. In this test method, plane waves are generated in a tube by a sound source, and the decomposition of the interference field is achieved by the measurement of acoustic pressures at two fixed locations using wall-mounted microphones or an in-tube traversing microphone, and subsequent calculation of the complex acoustic transfer function and quantities reported in the previous paragraph. The test method is intended to provide an alternative, and generally much faster, measurement technique than that of ISO 10534-1. Normal incidence absorption coefficients coming from impedance tube measurements are not comparable with random incidence absorption coefficients measured in reverberation rooms according to ISO 354. The reverberation room method will (under ideal conditions) determine the sound absorption coefficient for diffuse sound incidence. However, the reverberation room method requires test specimens which are rather large. The impedance tube method is limited to studies at normal and plane incidence and requires samples of the test object which are of the same size as the cross-section of the impedance tube. For materials that are locally reacting only, diffuse incidence sound absorption coefficients can be estimated from measurement results obtained by the impedance tube method (see Annex E).

This document specifies an engineering method for measuring the interior sound of road vehicles of categories M and N under typical driving conditions. It does not apply to agricultural tractors and field machinery. It specifies the conditions for obtaining reproducible and comparable measurements of sound pressure levels inside a vehicle. These measurements are used to obtain a representative average sound level during a typical driving cycle to enable assessment of adverse effects on human health. The results can be used for — standardized assessment of interior sound for comparisons (e.g. benchmark, consumer information programs), — verification tests, to decide whether or not the sound inside the vehicle is in accordance with specifications, — regulatory purposes, for example for evaluation of sound in relation to labour or for general health standards, and — monitoring tests, in order to check that the sound inside the vehicles has not changed since delivery, or between individual units of a consignment of vehicles. This document does evaluate the exposure to interior sound of vehicles in a way as it is commonly used for scientific effects on human health. It does not assess maximum interior sound of a vehicle under extreme driving situations, as today’s measured maximum sound pressure levels inside vehicles are far away from the risk to create instantaneous hearing damages.

This document specifies a method for estimating the loudness and loudness level of both stationary and time-varying sounds as perceived by otologically normal adult listeners under specific listening conditions. The sounds may be recorded using a single microphone, using a head and torso simulator, or, for sounds presented via earphones, the electrical signal delivered to the earphones may be used. The method is based on the Moore-Glasberg-Schlittenlacher algorithm. NOTE 1 Users who wish to study the details of the calculation method can review or implement the source code which is entirely informative and provided with the standard for the convenience of the user. This method can be applied to any sounds, including tones, broadband noises, complex sounds with sharp line spectral components, musical sounds, speech, and impact sounds such as gunshots and sonic booms. Calculation of a single value for the overall loudness over the entire period of a time-varying signal lasting more than 5 s is outside the scope of this document. NOTE 2 It has been shown that, for steady tones, this method provides a good match to the contours of equal loudness level as defined in ISO 226:2003[18] and the reference threshold of hearing as defined in ISO 389-7:2019[19].

This document specifies combinations of sound pressure levels and frequencies of pure continuous tones which are perceived as equally loud by human listeners. The specifications are based on the following conditions: a) the sound field in the absence of the listener consists of a free progressive plane wave; b) the source of sound is directly in front of the listener; c) the sound signals are pure tones; d) the sound pressure level is measured at the position where the centre of the listener's head would be, but in the absence of the listener; e) listening is binaural; f) the listeners are otologically normal persons in the age range from 18 years to 25 years inclusive. The data are given in graphical form in Annex A and in numerical form in Annex B for the preferred frequencies in the one-third-octave series from 20 Hz to 12 500 Hz, inclusive, in accordance with ISO 266.

This document specifies a method of comparing traffic noise on different road surfaces for various compositions of road traffic for the purpose of evaluating different road surface types. Sound levels representing either light or heavy vehicles at selected speeds are assigned to a certain road surface. The method is applicable to traffic travelling at constant speed, i.e. free-flowing conditions at posted speeds of 50 km/h and upwards. For conditions where traffic is not free flowing, such as at junctions and where the traffic is congested, the method is not applicable. A standard method for comparing the noise characteristics of road surfaces gives road and environment authorities a tool for establishing common practices or limits regarding the use of road surfaces meeting certain noise criteria. However, it is not within the scope of ISO 11819 (all parts) to suggest such criteria. The statistical pass-by (SPB) method is suitable for use for the following main purposes: — to classify road surfaces according to their influence on traffic noise (surface classification); — to assist in verifying conformity of production of road surfaces; — to evaluate acoustic performance of road surfaces throughout operation relative to new condition; — to evaluate the influence of different road surfaces on traffic noise at sites irrespective of condition and service time; — to evaluate acoustic performance of a road surface relative to a reference surface. Due to practical restrictions, the method cannot be applied at all possible locations. However, the backing board method can allow some locations to be tested that were not previously acceptable. Clause 5 gives a general description of the SPB method.

This document describes a method for the objective determination of the audibility of tones in environmental noise. This document is intended to augment the usual method for evaluation on the basis of aural impression, in particular, in cases in which there is no agreement on the degree of the audibility of tones. The method described can be used if the frequency of the tone being evaluated is equal to, or greater than, 50 Hz. In other cases, if the tone frequency is below 50 Hz, or if other types of noise (such as screeching) are captured, then this method cannot replace subjective evaluation. NOTE The procedure has not been validated below 50 Hz. The method presented herein can be used in continuous measurement stations that work automatically.

This document specifies an engineering method for measuring the noise emitted by road vehicles of categories M and N under typical urban traffic conditions. It excludes vehicles of category L1 and L2, which are covered by ISO 9645, and vehicles of category L3, L4, and L5, which are covered by ISO 362‑2. The specifications are intended to reproduce the level of noise generated by the principal noise sources during normal driving in urban traffic (see Annex A). The method is designed to meet the requirements of simplicity as far as they are consistent with reproducibility of results under the operating conditions of the vehicle. The test method requires an acoustical environment that is obtained only in an extensive open space. Such conditions are usually provided for — type approval measurements of a vehicle, — measurements at the manufacturing stage, and — measurements at official testing stations. NOTE 1 The results obtained by this method give an objective measure of the noise emitted under the specified conditions of test. It is necessary to consider the fact that the subjective appraisal of the noise annoyance of different classes of motor vehicles is not simply related to the indications of a sound measurement system. As annoyance is strongly related to personal human perception, physiological human conditions, culture, and environmental conditions, there is a large variation and it is, therefore, not useful as a parameter to describe a specific vehicle condition. NOTE 2 Spot checks of vehicles chosen at random are rarely made in an ideal acoustical environment. If measurements are carried out on the road in an acoustical environment that does not fulfil the requirements stated in this document, the results obtained can deviate appreciably from the results obtained using the specified conditions.

This document specifies an engineering method for measuring the noise emitted by road vehicles of categories M and N by using a semi anechoic chamber with a dynamometer installed. The specifications are intended to achieve an acoustical correlation between testing the exterior noise of road vehicles in a semi anechoic chamber and outdoor testing as described in ISO 362-1. This document provides all necessary specifications and procedures for indoor testing to obtain results which are comparable to typical run-to-run variations of measurements in today’s type approval tests. This document provides a method designed to meet the requirements of simplicity as far as they are consistent with the reproducibility of results under the operating conditions of the vehicle. NOTE 1 The results obtained by this method give an objective measure of the noise emitted under the specified conditions of test. It is necessary to consider the fact that the subjective appraisal of the noise annoyance of different classes of motor vehicles is not simply related to the indications of a sound measuring system. As annoyance is strongly related to personal human perception, physiological human conditions, culture, and environmental conditions, there is a large variation and annoyance is therefore not useful as a parameter to describe a specific vehicle condition. NOTE 2 If measurements are carried out in rooms which do not fulfil the requirements stated in this document, the results obtained can deviate from the results using the specified conditions.

This document specifies correction procedures for the effect of temperature on vehicle noise emission, as influenced by the tyre/road noise contribution. Temperatures considered are road and ambient air temperatures. The noise emission for which this document is applicable is measured by means of ISO 11819-1, or similar methods such as the American methods SIP and CTIM specified in References [3][4]. It is also applicable to other pass-by measurements conducted without acceleration, such as when testing tyres and vehicles on test tracks with ISO 10844[1] reference surfaces; however, given that tyre/road noise is dominant. Measurement results obtained at a certain temperature, which may vary over a wide range, are normalized to a designated reference temperature (20 °C) using a correction procedure specified in this document.

This method objectively categorises sources by determination of the prominence of impulsive sound, with the aim of correlating to community response. This method for measuring the prominence of impulsive sounds is intended for sources not identified as gunfire or high-energy impulsive sound. It typically produces adjustments in the range 0,0 dB to 9,0 dB. These adjustments are intended to be used to categorise the sources as either regular impulsive or highly impulsive sound sources and apply the penalty indicated in ISO 1996-1. However, the adjustments may be applied directly, as is done in NT ACOU 112[2], and BS 4142[3]. ISO 1996-2 provides additional guidance for performing these measurements. The method is intended for use on sources with impulsive characteristics that are not already categorised in ISO 1996-1. A non-exhaustive list of examples includes compressed air release, scrap handling, goods delivery, fork lifts with rattling forks, skateboard ramps, industrial shearing, gas discharges, percussive tools in demolition, powered riveting, etc. The method is not intended for use on sounds from firearms. Although the measurements of prominence may give relevant results, research has shown the response to these sources is influenced by factors outside of the scope of this document. In addition, the method is not intended to use for high-energy impulsive sound sources as specified in ISO 1996-1. NOTE This method is not intended for occupational hearing loss, which is outside the scope of this document. See Annex A for recommended additional research.

This document specifies basic methods for speech recognition tests for audiological applications. NOTE Examples of speech materials are given in Annex A. In order to ensure minimum requirements of precision and comparability between different test procedures including speech recognition tests in different languages, this document specifies requirements for the composition, validation and evaluation of speech test materials, and the realization of speech recognition tests. This document does not specify the contents of the speech material because of the variety of languages. Furthermore, this document also specifies the determination of reference values and requirements for the realization and manner of presentation. In addition, there are features of speech tests described which are important to be specified, but which are not understood as a requirement. This document specifies procedures and requirements for speech audiometry with the recorded test material being presented by an audiometer through a transducer, e.g., an earphone, bone vibrator, or loudspeaker arrangement for sound field audiometry. Methods for using noise either for masking the non-test ear or as a competing sound are described. Some test subjects, for example children, can require modified test procedures not specified in this document. Specialized tests, such as those used for evaluating directional hearing and dichotic hearing, are outside the scope of this document.

This document describes a test method for measuring in situ the sound absorption coefficient of road surfaces as a function of frequency in the range from 250 Hz to 4 kHz. Normal incidence is assumed. However, the test method can be applied at oblique incidence although with some limitations (see Annex F). The test method is intended for the following applications: — determination of the sound absorption properties of road surfaces in actual use; — comparison of sound absorption design specifications of road surfaces with actual performance data of the surface after completion of the construction work. The complex reflection factor can also be determined by this method.

This document specifies a method for the measurement of room acoustic parameters in unoccupied open-plan offices. It specifies measurement procedures, the apparatus needed, the coverage required, the method for evaluating the data, and the presentation of the test report. This document describes a group of single-number quantities indicating the room acoustic performance of an open-plan office in a condition when one person is speaking. They focus on spatial decay of speech while the quantities in ISO 3382-2 focus on temporal decay of sound.

This document specifies the essential characteristics of a test track surface intended to be used for measuring rolling sound emission of vehicles and their tyres. The surface design given in this document — produces consistent levels of tyre or road sound emission under a wide range of operating conditions including those appropriate to vehicle sound testing, — minimizes inter-site variation, — limits absorption of the vehicle sound sources, and — is consistent with road-building practice.

This document describes methods for checking laser profilometer performance with respect to the capability of such equipment in measuring pavement texture. The objective of this document is to make available an internationally accepted procedure by which performance of various laser-based equipment for pavement texture measurements can be evaluated. The document includes guidelines and recommendations intended to assist users of laser profilometers in verification of their equipment. This document is not intended as the basis for qualifying or approving laser profilometers. The procedure aims at providing tools for verifying that such systems perform satisfactory in all respects important for the correct measurements of texture, as well as to detect when and in what way the performance is unsatisfactory. This document also provides some general information about the limitations and trade-offs of laser profilometer systems. Modern profilometers in use for measurements on pavements are almost entirely of the contactless type (such as laser point or line triangulation) designed for two- or three-dimensional measurements, and this document is intended for evaluating the performance of this type of profilometers. However, some other contactless types of profilometer can use applicable parts of ISO 13473. This document has been prepared as a result of a need identified to correct for unacceptable differences in results measured by various equipment, even if the operators of these claim that they meet the applicable part of ISO 13473. It is not intended for other applications than pavement texture measurement. To be able to exclude errors influenced by programming mistakes or wrong interpretation of ISO 13473‑1 a reference program code, digital profiles and calculated reference MPD-values can be reached via Annex A. This document is a complement to other parts of ISO 13473 in which some specifications are given but methods to check them are not included.

This document specifies differentiated criteria for acoustic conditions and characteristics for rooms and spaces used for music rehearsal. The criteria are specified for different types of music, regardless of the type of building in which the spaces are located. The document provides criteria for room acoustics in spaces used for music rehearsal, whether this is the primary use of the spaces or they are multi-purpose spaces. Together with the acoustic criteria, requirements are given for net room height, net room volume and net area. Criteria for acoustic conditions are differentiated on the basis of three music types: amplified music, quiet acoustic music, and loud acoustic music. This document is applicable to the planning of new buildings and the refurbishment of existing ones. The document can also be used to assess the suitability of existing spaces for different musical purposes. The document can be used for the adjustment of rooms and spaces whose primary purpose is not music rehearsal such as sports halls, classrooms, assembly halls, multi-purpose rooms, etc. Flexible acoustic solutions can be used in order to cover several purposes of use. The criteria in this document do not apply to large, specialized concert halls, opera venues and similar spaces which are basically designed for concerts and performances, or specialized music recording studios. The document does not deal with the need for logistics, storage rooms for instruments and other key support functions relating to music rehearsal. Sound insulation criteria are not included in this document.

This document specifies the measurement method and conditions to obtain reproducible noise levels on-board all kinds of vehicles operating on rails or other types of fixed track, hereinafter conventionally called “unit”, except for track maintenance vehicles in working modes. This document is applicable to type testing. It does not include all the instructions to carry out monitoring testing or evaluation of noise exposure of passengers or drivers over a whole journey. This document is not applicable to guided buses. It provides measurement procedures for vehicle interior noise (in general, a vehicle type test is carried out using only a selected subset of these tests): — when the vehicle is moving at constant speed; — when the vehicle is stationary; — when the vehicle is accelerating or decelerating; — in the driver's cab when an external warning horn is sounding (specifically required for European Union regulation application) It does not provide measurement procedures for: — audibility or intelligibility of any audible signals; — assessment of warning devices other than warning horns. The assessment of noise exposure of train crew due to operational conditions is not in the scope of this document. The results can be used, for example: — to characterise the noise inside these units; — to compare the internal noise of various units on a particular track section; — to collect basic source data for units. The test procedures specified in this document are of engineering grade (grade 2), the preferred grade for noise declaration purposes as defined in ISO 12001. If test conditions are relaxed, for example as they are for monitoring of in-service trains, then the results are no longer of engineering grade. The procedures specified for accelerating and decelerating tests are of survey grade (grade 3).

This document specifies a method to predict the dynamic forces generated by an active component on a receiving structure from measurement on a test bench. It sets out the requirements applicable to test benches and setup measurement conditions of dynamic forces: a criterion of validity of transfer functions measurements can be established for example. The objective is to evaluate noise and vibrations generated by active components mounted on receiving structures, including the possibility to optimise vibration isolators. It can be applied to different systems connected to a building, such as a compressor or a power generator, or to systems connected to a vehicle body, such as an engine powertrain or an electrical actuator, for example.

This document specifies field survey methods for measuring a) airborne sound insulation between rooms, b) impact sound insulation of floors, c) airborne sound insulation of façades, and d) sound pressure levels in rooms caused by service equipment. The methods described in this document are applicable for measurements in rooms of dwellings or in rooms of comparable size with a maximum of 150 m3. For airborne sound insulation, impact sound insulation and façade sound insulation the method gives values which are (octave band) frequency dependent. They can be converted into a single number characterising the acoustical performances by application of ISO 717-1 and ISO 717-2. For heavy/soft impact sound insulation, the results also are given as A-weighted maximum impact sound pressure level. For service equipment sound the results are given directly in A - or C -weighted sound pressure levels.

This document specifies methods for recording the time history of the sound pressure produced either by shooting with calibres of less than 20 mm, or by detonation of explosive charges of less than 50 g TNT equivalent, within the shooting range at locations of interest, regarding the exposure to sound of the shooter, or any other person within the shooting range. The time history of the sound pressure can be the basis for further analyses of this type of sound at the locations of interest.

This document provides specifications for socio-acoustic surveys and social surveys which include questions on noise effects (referred to hereafter as “social surveys”). It includes questions to be asked, response scales, key aspects of conducting the survey, and reporting the results. It is recognized that specific requirements and protocols of some social studies may not permit the use of some or all of the present specifications. This document in no way lessens the merit, value or validity of such research studies. The scope of this document is restricted to surveys conducted to obtain information about noise annoyance “at home”. Surveys conducted to obtain information about noise annoyance in other situations, such as recreational areas, work environments and inside vehicles, are not included. This document concerns only the questions on noise annoyance used in a social survey and the most important additional specifications needed to accomplish a high level of comparability with other studies. Other elements which are required to provide high-quality social surveys, but which are not specific for social surveys on noise (such as sampling methods), can be found in textbooks (see References [1] and [2]). Conformity with the recommendations of this document does not guarantee the collection of accurate, precise or reliable information about the prevalence of noise-induced annoyance and/or its relationship to noise exposure. Other aspects of study design, as well as uncertainties of estimation and measurement of noise exposure, can influence the interpretability of survey findings to a great extent.

This document specifies methodology for qualifying acoustic spaces as anechoic and hemi-anechoic spaces meeting the requirements of a free sound field. This document specifies discrete-frequency and broad-band test methods for quantifying the performance of anechoic and hemi-anechoic spaces, defines the qualification procedure for an omni-directional sound source suitable for free-field qualification, gives details of how to present the results and describes uncertainties of measurement. This document has been developed for qualifying anechoic and hemi-anechoic spaces for a variety of acoustical measurement purposes. It is expected that, over time, various standards and test codes will refer to this document in order to qualify an anechoic or hemi-anechoic space for a particular measurement. Annex D provides guidelines for the specification of test parameters and qualification criteria for referencing documents. In the absence of specific requirements or criteria, Annex A provides qualification criteria and measurement requirements to qualify anechoic and hemi-anechoic spaces for general purpose acoustical measurements. This document describes the divergence loss method for measuring the free sound field performance of an acoustic environment.

This document specifies test requirements for the laboratory measurement of the sound insulation of building elements and products, including detailed requirements for the preparation and mounting of the test elements, and for the operating and test conditions. It also specifies the applicable quantities, and provides additional test information for reporting. The general procedures for airborne and impact sound insulation measurements are given in ISO 10140‑2 and ISO 10140-3, respectively.

This document provides technical guidance to achieve acoustic quality of open office spaces to support dialogue and formal commitment between the various stakeholders involved in the planning, design, construction or layout of open-plan workspaces: end customers, project owners, prescribers, consultants, etc. It is applicable to all open-plan offices in which the following activities are performed: — Space type 1: activity not known yet – vacant floor plate; — Space type 2: activity mainly focusing on outside of the room communication (by telephone/audio/video); — Space type 3: activity mainly based on collaboration between people at the nearest workstations; — Space type 4: activity based on a small amount of collaborative work; — Space type 5: activity that can involve receiving public; — Space type 6: combining activities within the same space. More specifically, this document applies to refitting projects of existing business sites (renovation and/or change or add activities) and layout projects for new spaces and spaces delivered unfurnished. It covers both the activities and the operations of the following stakeholders: — end customers: diagnosis, survey, expression of needs in keeping with their knowledge in the area of acoustics; — project owners: drafting contract specifications; — project management companies (architects, acousticians, ergonomists, economists and consulting engineers): indicating the performance of acoustic solutions and the layout principles used to achieve the result expressed in the specifications; — building traders: reaching a clear and verifiable target with respect to the choices of materials and implementation; — Building developer: promoting indoor environmental quality, including acoustic comfort, in estate operations in order to use it as a competitive element; — specialists in occupational health, safety and quality; — expert assessments and consultancy.

This document describes criteria and procedures for acoustic classification of dwellings. The purpose of this document is to make it easier for developers to specify a classified level of acoustic quality for a dwelling, and help users and builders to be informed about the acoustic conditions and define increased acoustic quality. The document can also be applied as a general tool to characterize the quality of the existing housing stock and includes provisions for classifying the acoustic quality before and after renovation has taken place. By the acoustic quality for a dwelling is understood the quality of the acoustic performances typically included in building regulations, e.g. sound insulation towards neighbouring premises and road traffic as well as sound from service equipment. Sound insulation and room acoustics internally in a dwelling are not included in the acoustic classes defined. This document does not have a legal status in a country, unless decided by its own authorities. However, an additional purpose of this document is to help national authorities and standardization organisations to develop or revise national building regulations and acoustic classification schemes. For the purpose of this document, the term ”dwellings” refers to detached and attached dwelling-houses, buildings with several flats as well as individual dwellings, and a dwelling is the living space for a household.