# Regulatory references: environmental and building acoustics > A reasoned inventory of the Italian statutes and the ISO, IEC and UNI standards in force for environmental and building acoustics: edition in force, scope, scope limits and revision status, verified at source. Published: 2026-08-26 Practice: acustica Standard: Statutes and technical standards for environmental and building acoustics Page: --- **In brief.** Italian laws and decrees on environmental and building acoustics apply on their own, within their scope and from their entry into force; ISO, IEC and UNI technical standards are voluntary and become binding only when a decree cites them, a contract adopts them or a court uses them as a criterion. A decree that cites a standard freezes that edition: editions withdrawn by their bodies years ago are still in force in Italy, and a report should cite the UNI EN ISO / CEI EN adoption in force, not just the international designation. **Statutes and decrees** apply whether or not a party invokes them, within their own scope and from their date of entry into force. **Technical standards** — ISO, IEC, UNI — are not statutes: they are voluntary, and become binding in three ways: when a decree invokes them, when a contract adopts them, or when a court takes them as the assessment criterion. It is the same document; what changes is the basis on which it applies, and that basis belongs in the report. The first of the three has a consequence that changes everything, set out in [Technical standards invoked by a statute](#technical-standards-invoked-by-a-statute): the decree freezes the edition it names, so standards the issuing body withdrew twenty years ago are in force in Italy. In Italy, ISO and IEC standards enter the technical framework **as adopted** UNI EN ISO and CEI EN documents, with their own number and year, which can differ from the international ones. The tables below cite the ISO and IEC designations, which identify the technical document; in a report it is better to cite the adoption in force where one exists, because that is the document an opposing party will look for. ## Who intervenes, and in what order Before the standards it helps to know who to turn to. The chain is not hierarchical: it is a sequence of distinct competences, and skipping a link usually lengthens the process rather than shortening it. | # | Body | What it does | Source | |---|---|---|---| | **1** | **Municipality** — environment office or one-stop business desk | Receives the complaint and runs the procedure. It holds the **administrative control** over compliance: checks at building-permit, operating-authorisation and licence stage | [Law 447/95](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:legge:1995-10-26;447) Art. 14 | | **2** | **Local Police** | On-site ascertainment and reports. It does not perform sound measurements of evidential value: it records the facts | Municipal by-laws | | **3** | Regional **ARPA** | The **technical body**: it performs the measurements and assessments at the authority's request. It is ARPA's finding that provides the technical basis for the mayor's order | [Law 447/95](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:legge:1995-10-26;447) Art. 14 | | **4** | **Province / Metropolitan City** | Surveillance and control at **supra-municipal** level, drawing on ARPA. Competent where the source or its effect crosses municipal boundaries | [Law 447/95](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:legge:1995-10-26;447) Art. 14 | | **5** | **Mayor** | **Order** (*ordinanza*) limiting or suspending the activity. It is the **Mayor's exclusive** competence, not delegable to a senior official — case law has annulled orders signed by officials for lack of competence | [Law 447/95](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:legge:1995-10-26;447) Art. 9 | | **6** | **ASL** — prevention department | Public-health aspects, and for noise **in the workplace** the enforcement of Title VIII (PSAL/SPISAL services, named differently by Region) | [Leg. Decree 81/08](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:decreto.legislativo:2008-04-09;81) | | **7** | **National Labour Inspectorate** | Enforcement on worker exposure, jointly with the ASL | [Leg. Decree 81/08](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:decreto.legislativo:2008-04-09;81) | | **8** | **Judicial police and Public Prosecutor** | The **criminal** route, where the facts may fall under Article 659 of the Criminal Code: it requires the potential to disturb an indeterminate plurality of persons | [Art. 659 Criminal Code](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:regio.decreto:1930-10-19;1398) | | **9** | **Civil court** | The **civil** route between private parties, on a party's initiative: normal tolerability of emissions | [Art. 844 Civil Code](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:regio.decreto:1942-03-16;262) | Three things this table makes explicit. **The technician and the authority are different links.** A party's report, even signed by a qualified technician on the ENTECA register, is not an official finding: it serves to ground a complaint or a defence. The finding with administrative effect is made by ARPA on the authority's instruction. **The three routes — administrative, criminal, civil — are independent and can run together.** Each has a different threshold condition, and the outcome of one does not decide the others: a mayor's order can issue without any offence, and a finding on normal tolerability can stand without any administrative limit being exceeded. **For worker noise the chain is a different one.** It does not run through the Municipality or ARPA: enforcement lies with the ASL and the Labour Inspectorate, and the source is Legislative Decree 81/08, not Law 447/95. ## European directives Directives do not apply directly: they apply through the Italian instrument that transposes them. Citing them is useful when the counterparty is foreign, or when the *rationale* of a threshold is under discussion. | Directive | Subject | Italian transposition | |---|---|---| | **[2002/49/EC](https://eur-lex.europa.eu/eli/dir/2002/49/oj)** | Assessment and management of environmental noise | **Legislative Decree 194/2005** — strategic noise maps and action plans | | **[2003/10/EC](https://eur-lex.europa.eu/eli/dir/2003/10/oj)** | Worker exposure to noise | **Legislative Decree 81/2008, Title VIII Chapter II** — action values and limit value on LEX,8h | | **[2002/44/EC](https://eur-lex.europa.eu/eli/dir/2002/44/oj)** | Worker exposure to mechanical vibration | **Legislative Decree 81/2008, Title VIII Chapter III** — values on A(8), hand-arm and whole-body | ## Statutes and decrees: environmental acoustics | Reference | Subject | Scope | |---|---|---| | **[Law 447 of 26/10/1995](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:legge:1995-10-26;447)** | Framework law on noise pollution | General principles, competences of State/Regions/Provinces/Municipalities, acoustic zoning of the territory, the qualified technician. It sets no limit values: those are delegated to implementing decrees | | **[DPCM 14/11/1997](https://www.gazzettaufficiale.it/eli/id/1997/12/01/097A9602/sg)** | Limit values for sound sources | The six land-use classes are in **Table A**; the absolute immission limit values in **Table C**, emission in B, quality values in D. The differential criterion in dwellings is in **Article 4** (5 dB by day, 3 dB by night) with its exemptions. A report cites the table, not the decree | | **[Ministerial Decree 16/03/1998](https://www.gazzettaufficiale.it/eli/id/1998/04/01/098A2679/sg)** | Detection and measurement techniques | Measurement methodology, instrumentation, duration and representativeness, determination of tonal and impulsive components and the corresponding penalties | | **[Presidential Decree 142 of 30/03/2004](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:decreto.presidente.repubblica:2004-03-30;142)** | Road traffic noise | Buffer strips and limits for road infrastructure, distinguishing new roads from existing or assimilable ones | | **[Presidential Decree 459 of 18/11/1998](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:decreto.presidente.repubblica:1998-11-18;459)** | Railway noise | Buffer strips and limits for railway infrastructure, implementing Article 11 of Law 447/95 | | **[Ministerial Decree 31/10/1997](https://www.gazzettaufficiale.it/eli/id/1997/11/15/097A9090/sg)** | Airport noise — measurement methodology | Official Gazette 15 November 1997. It introduces the **LVA** descriptor (airport noise evaluation level), defines the **airport surroundings** as the territory within the **60 dB(A) LVA** contour, and establishes airport acoustic zoning as a planning instrument | | **[Ministerial Decree 03/12/1999](https://www.gazzettaufficiale.it/eli/id/1999/12/10/99A10551/sg)** | Airports — anti-noise procedures and protection zones | Official Gazette 10 December 1999. It defines the three protection zones **A**, **B** and **C** by LVA range, with the prevalent land uses admitted in each, and the anti-noise procedures for take-off and landing | | **[Presidential Decrees 496 of 11/12/1997](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:decreto.presidente.repubblica:1997-12-11;496)** and **[476 of 09/11/1999](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:decreto.presidente.repubblica:1999-11-09;476)** | Civil aircraft — noise reduction | 496 is the regulation on reducing noise pollution from civil aircraft; 476 amends it on night-flight bans | | **[Ministerial Decree 20/05/1999](https://www.gazzettaufficiale.it/eli/id/1999/09/24/099A7954/sg)** | Airports — monitoring systems | Criteria for the design of airport noise monitoring systems and for airport classification | | **[Ministerial Decree 29/11/2000](https://www.gazzettaufficiale.it/eli/id/2000/12/06/00A15030/sg)** | Noise containment and abatement plans | Official Gazette 6 December 2000. Criteria for the plans owed by operators of public transport services and infrastructure — roads, railways and airports. It is the decree that turns an established exceedance into an obligation to act within a stated horizon | | **[Legislative Decree 194 of 19/08/2005](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:decreto.legislativo:2005-08-19;194)** | Strategic noise mapping | Implements Directive 2002/49/EC: strategic noise maps for agglomerations above 250,000 inhabitants and mapping for major road and rail axes, with five-yearly action plans | | **[Legislative Decree 42 of 17/02/2017](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:decreto.legislativo:2017-02-17;42)** | Qualified acoustics technician | Requirements for recognition of the qualification; Article 21 establishes the ENTECA national register at the Ministry of the Environment, fed by the Regions and published through ISPRA | | **[DPCM 01/03/1991](https://www.gazzettaufficiale.it/eli/id/1991/03/08/091A1149/sg)** | Maximum noise exposure limits | **Historical, with residual application.** It predates the framework law and is largely superseded: Article 6 sets immission limits for municipalities that have **not adopted acoustic zoning**. Transitional regime: 70/60 dB(A) nationwide, 65/55 in zone A, 60/50 in zone B, 70/70 in exclusively industrial zones (day/night) | | **[DPCM 31/03/1998](https://www.gazzettaufficiale.it/eli/id/1998/05/26/098A4373/sg)** | General criteria for practising as a qualified acoustics technician | **Historical: superseded by Legislative Decree 42/2017**, which is the reference in force. It is here because a certificate issued under that regime is a document still encountered. Act of guidance and coordination, Official Gazette no. 120 of 26 May 1998, issued under Art. 3(1)(b) and Art. 2(6)(7)(8) of Law 447/95. It governed the **regional recognition** of the qualification: the application went to the environment department of the applicant's Region, which issued the certificate. This is the regime superseded by Legislative Decree 42/2017, which centralised the register | | **[Legislative Decree 81 of 09/04/2008, Title VIII](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:decreto.legislativo:2008-04-09;81)** | Worker exposure | Chapter II: noise, with action values and a limit value on daily exposure LEX,8h. Chapter III: vibration, with action and limit values on A(8) for hand-arm and whole-body | ### Airport noise has a descriptor of its own The three transport infrastructures have three distinct frameworks, and they are not interchangeable: the descriptor, the geometry and the governing act all change. | Infrastructure | Source | Descriptor | Geometry | |---|---|---|---| | **Road** | [Presidential Decree 142/2004](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:decreto.presidente.repubblica:2004-03-30;142) | LAeq day and night | Buffer strips at a fixed distance from the road boundary, width by road type, with separate limits for new and existing roads | | **Rail** | [Presidential Decree 459/1998](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:decreto.presidente.repubblica:1998-11-18;459) | LAeq day and night | A 250 m buffer strip each side, measured from the centreline of the outer rail and split into a 100 m **strip A** and a 150 m **strip B** with different limits. It applies to existing lines and to new lines up to 200 km/h | | **Airport** | Ministerial Decrees [31/10/1997](https://www.gazzettaufficiale.it/eli/id/1997/11/15/097A9090/sg) and [3/12/1999](https://www.gazzettaufficiale.it/eli/id/1999/12/10/99A10551/sg) | **LVA** | Airport surroundings within the 60 dB(A) LVA contour, divided into protection zones A, B and C | The airport is the one that departs furthest, on two points that change the work. **The descriptor.** Not LAeq over the daytime and night-time reference periods, but **LVA**, a quantity built on airport operations. An LVA value and an LAeq,TR value are comparable neither with each other nor with the DPCM 14/11/1997 tables. **The geometry.** There are no buffer strips at a fixed distance from the axis as for roads and railways: there is an **airport surrounding** bounded by the 60 dB(A) LVA contour, divided into protection zones A, B and C by Ministerial Decree 3/12/1999, each with its admitted land uses. It is a zoning of its own, standing alongside municipal acoustic classification rather than replacing it. The contours are updated by the operator and checked by the airport commissions; the current list of sector references is maintained by [ENAC](https://www.enac.gov.it/ambiente/impatto-ambientale/le-emissioni-acustiche-rumore/rumore-principali-riferimenti-normativi/). ### Immission limits run through municipal zoning The DPCM 14/11/1997 values do not apply directly to an address: they apply to the **acoustic class** that address falls in, and the classification is adopted by the Municipality. Before comparing a level with a limit, the class has to be established — and whether the Municipality has approved a zoning plan at all: if it has not, the transitional regime of Article 6 of DPCM 1/3/1991 applies, with different limits. "The limit is 55 dB(A)" says nothing without the class. It is also why a calculation tool, this site included, can at most compare a number with a threshold chosen by hand. ### The differential criterion has applicability thresholds The two thresholds of the differential criterion are 5 dB by day and 3 dB by night. Whether the criterion applies at all is decided by Article 4 of DPCM 14/11/1997, which **excludes** it when the ambient level is low: **50/40 dB(A) with windows open**, **35/25 dB(A) with windows closed** (day/night). Below those values the noise is deemed negligible and the differential is not assessed. The detail is on the dedicated [differential criterion](/en/wiki/criterio-differenziale/) page. Quoting 5 and 3 without the exemptions makes the criterion look always applicable. ### Administrative and civil are two distinct judgements The differential criterion and the zone limits belong to **administrative** law: whoever breaches them answers to the authority. Between private parties the case rests instead on **Article 844 of the Civil Code**, the normal tolerability of emissions, which is a different criterion assessed by the judge case by case. The two paths do not coincide, in either direction. Meeting the administrative limits does not rule out that an emission exceeds normal tolerability; exceeding an administrative limit does not by itself decide a civil case. A report intended for court has to say which of the two planes it sits on, because they are two different questions put to two different judges. The sources for those two planes are in the dedicated section below. ### The qualified technician, concretely Legislative Decree 42/2017 does more than name the role. Registration in the national list requires a technical or scientific degree and a qualifying course of **at least 180 hours, of which at least 60 of practical exercises**, with a final assessment; maintaining it requires **at least 30 hours** of continuing education every five years, spread over a minimum of three. The list is managed by the Ministry of the Environment and Energy Security and published through ISPRA's ENTECA platform. The technical activities under Law 447/95 are reserved to those on the register. A calculation run by anyone remains a calculation; an assessment meant to have effect is signed by a registered technician, who answers for it. No software changes that, and "certified software" is not a category the Italian framework provides for. ## Statutes and decrees: building acoustics | Reference | Subject | Scope | |---|---|---| | **[DPCM 05/12/1997](https://www.gazzettaufficiale.it/eli/id/1997/12/22/97A10190/sg)** | Passive acoustic requirements of buildings | In force since **20 February 1998**. Sets minimum values for the sound reduction index of partitions between units, façade sound insulation, impact sound pressure level, and noise from continuously and intermittently operating service equipment. It applies to buildings whose permit postdates entry into force | | **[Ministerial Decree 24/11/2025](https://www.gazzettaufficiale.it/eli/id/2025/12/03/25A06516/SG)** | Minimum Environmental Criteria for construction | Published in Official Gazette no. 281 of 3 December 2025, **in force since 1 February 2026**. Repeals Decree 256/2022 and the corrective Decree of 5 August 2024. In public works it makes internal-acoustics requirements binding, to be demonstrated at design stage and verified on completion. **Criterion 2.3.10** requires reaching at least **class II of UNI 11367** (tables 1 and 2) | DPCM 5/12/1997 and UNI 11367 **are not the same thing and do not replace each other**, and they are frequently confused. The decree sets a binding minimum threshold, the same for everyone. The UNI standard defines a voluntary scale of classes: a building can meet the decree and land in class III or IV. Saying "classified in class II" does not say the decree is met, and saying "compliant with the DPCM" does not assign a class. ### History of the acoustic references for schools They still turn up in reports and tender documents, and whoever meets them needs to know where the path ended. | Reference | What it set | Status | |---|---|---| | **[Circular of the Ministry of Public Works no. 3150 of 22/05/1967](https://www.edscuola.it/archivio/norme/circolari/cmlp_22567.pdf)** | "Criteria for assessing and commissioning acoustic requirements in school buildings": it set a **maximum reverberation time of 1.2 s** | **Historical.** It is the figure most often quoted out of context: a single number, with no dependence on volume or frequency band | | **[Ministerial Decree of Public Works 18/12/1975](https://www.indicenormativa.it/norma/urn:nir:ministero.lavori.pubblici:decreto:1975-12-18)** | "Updated technical standards for school building": dimensional criteria for classrooms, lighting, ventilation, floor area per pupil, and the acoustic requirements | **Not applicable since 3 February 1996**, by effect of Article 12 of **Law 23/1996**, save as provided by Article 5(3) of that same law. Published in the Ordinary Supplement to Official Gazette no. 29 of 2 February 1976 | **Where the path ended.** The binding insulation requirements now sit in **DPCM 5/12/1997**; the internal acoustic quality of classrooms — reverberation and intelligibility — in **UNI 11532-2:2020**, which the CAM invoke explicitly for schools; and in public works **Ministerial Decree 24/11/2025** makes at least class II of UNI 11367 binding. **Why the difference matters.** A single 1.2 s T60 and a per-octave-band requirement depending on classroom volume are not the same constraint, and do not yield the same design: the former can be met by a classroom that remains unintelligible at the frequencies carrying the consonants. If a tender document still shows the 1967 figure, the first thing to settle is which requirement is being adopted. ## Shows, events and dance venues Here noise is the service being sold, not a by-product of production, and the framework is its own. Two planes not to be confused: protecting **those inside** and protecting **those outside**. | Reference | Subject | Notes | |---|---|---| | **[DPCM 215 of 16/04/1999](https://www.gazzettaufficiale.it/eli/id/1999/07/02/099G0206/sg)** | Acoustic requirements for sound sources in dancing-entertainment venues, public-performance venues and licensed premises | Official Gazette no. 153 of 2 July 1999, in force from **17 July 1999**. **Article 2** sets the maximum levels inside the venue: **105 dB(A) LASmax** and **95 dB(A) LAeq** from 1 June 1999 for public-performance and dancing-entertainment venues (six months from entry into force for other licensed premises), with LASmax falling to **103 dB(A)** at twelve months and **102 dB(A)** at twenty-four months. Indices and instrumentation — class 1 — refer to **Ministerial Decree 16/03/1998**. Measurement in **Articles 4 and 5** and in **Annex A** | | **[ISPRA application guidelines](https://www.isprambiente.gov.it/contentfiles/00003500/3530-manuali-2001-05.pdf/)** | Application of DPCM 215/1999 | An ISPRA manual. It is not a standard: it counts as an interpretative source, and it is the document enforcement bodies use in practice | | **[Law 447/95 Art. 6(1)(h)](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:legge:1995-10-26;447)** | Municipal authorisations for **temporary activities** and events in public places | It is the basis of the derogation: concerts, festivals, fairs and construction sites are authorised in derogation from the limits, on criteria set by Regions and Municipalities | Three distinct planes, and an assessment that mixes them is of no use. **Inside and outside are two checks.** DPCM 215/1999 protects the audience inside the venue; the DPCM 14/11/1997 limits and the differential criterion protect receivers outside. Meeting one says nothing about the other, and a report covering only one must say which. **Staff are a third plane.** Anyone working in a dance venue or on a stage is an exposed worker: **Legislative Decree 81/08, Title VIII Chapter II** applies, with its own LEX,8h and action values, and enforcement runs through the ASL and the Labour Inspectorate rather than the Municipality. **Temporary activities live on derogation, and the derogation is municipal.** How many evenings, which hours, which levels, with how much notice: this is not in national law, it is in the regional statute and the municipal by-law. It is the first thing to obtain, before any calculation. ## Wind farms A source with a framework of its own, and not arbitrarily so: the noise of a wind turbine varies with wind speed — the same quantity that drives the background noise. Measuring it with the ordinary procedure does not work. | Reference | Subject | Notes | |---|---|---| | **[Ministerial Decree 1 June 2022](https://www.gazzettaufficiale.it/eli/id/2022/06/16/22A03580/sg)** | Criteria for measuring wind-farm noise | Italian Ministry for Ecological Transition, Official Gazette no. 139 of 2022. Covers mini and macro wind, both in verification and **at prediction stage**. It requires long measurement times and **continuous, simultaneous recording** of sound levels and meteorological parameters throughout. The choice of measurement periods rests on the site's **anemological characterisation** — wind rose and Weibull distribution of hub-height wind speed | | **[Ministerial Decree 10 September 2010](https://www.gazzettaufficiale.it/eli/id/2010/09/18/10A11230/sg)** | Guidelines for authorising renewable-energy plants | Siting criteria and criteria for insertion into the landscape and territory, invoked in authorisation procedures | | **[IEC 61400-11:2012](https://webstore.iec.ch/en/publication/5428)** | Wind turbines — acoustic noise measurement techniques | **Edition 3.0**. Adopted in Italy as **CEI EN 61400-11** (1 July 2014). It is the procedure by which the manufacturer declares the sound power level LWA at hub height: measurement close to the machine, to avoid propagation errors while allowing for the finite source size. It is part of the documentation the manufacturer delivers | Three points that decide a wind-farm assessment. **The plant is a fixed source.** It follows that the **differential criterion** of DPCM 14/11/1997 applies, with one particularity: the assessment is carried out **at building façades**. **Wind moves the source and the background together.** The turbine level rises with wind speed, and so does the noise of vegetation and of obstacles around the microphone. Without the simultaneous meteorological recording that the 2022 decree requires, the difference between the two is not determinable — and it is the difference, not the level, that the differential criterion assesses. **The nameplate LWA is not the level at the receiver.** IEC 61400-11 measures close to the machine by construction. Getting to the receiver is a propagation calculation, and over wind-farm distances the limits of ISO 9613-2 weigh more than they do for a nearby industrial source: this is the case where the choice of model has to be declared alongside the result. ## The regional and municipal layer The tables above are national, and they are not enough. Between the statute and the site there are two layers that decide what actually applies: - **Regional statutes and executive resolutions.** Law 447/95 assigns the Regions their own competences, and every Region has legislated: criteria for acoustic zoning, procedures for impact and climate assessments, technician requirements, derogations for temporary activities and construction sites. Much of this **sits not in the regional statute but in executive resolutions** (*delibere di Giunta*) which the statute invokes and which have to be obtained separately. Two identical sites in two different Regions can face different procedures. - **The municipal council resolution approving the PCA.** The Acoustic Zoning Plan is the act assigning a class to each portion of the territory, and it takes effect through the resolution that approves it: that resolution, with its number and date, is the source to cite — not "the municipality's zoning". The PCA also sets the transition strips between non-contiguous classes and the areas designated for temporary events. - **Municipal urban-policing and acoustics by-laws.** Hours, noisy activities, derogations for sites and events: these live here, not in the PCA, and they are the source that decides whether an activity is allowed in a given time band. - **The municipal noise abatement plan.** Provided for by **Article 7 of Law 447/95**, it is an instrument distinct from the PCA and mandatory in two cases: where limit values are exceeded, and where the zoning places adjacent areas more than 5 dB of class apart. It sets out the interventions, their priority and their funding. For a designer it is the source that says whether an area is already covered by a programmed intervention — information that changes the assessment of a new development. **Zoning is not universal, and whether it exists must be checked.** Without an approved PCA the DPCM 14/11/1997 limits cannot be applied and the transitional regime of Article 6 of DPCM 1/3/1991 takes over — with different values, given in the table above. Where to look: the municipality's official register and website for the resolution and the maps; the regional portal or the competent ARPA, which publish the progress of zoning across the territory; and in many Regions a catalogue of approved PCAs. **What to ask the Municipality for, concretely.** These are public documents, and where they are not already published they are obtained through a freedom-of-information request: - the **resolution approving the PCA** and the classification **maps**, with the accompanying technical report; - the **municipal noise abatement plan**, if adopted, and the implementation status of the works it provides for; - the **municipal by-law** on acoustics and the urban policing by-law, with hours and prescriptions for noisy activities; - the **criteria and forms for derogation authorisations** for temporary activities, construction sites and events; - any **transition strips** between non-adjacent classes and the areas designated for events, which the PCA identifies by name. **Operational consequence: before opening a national table, obtain the resolution approving the municipality's PCA and check the regional framework, executive resolutions included.** Neither is in this page, and neither can be derived from the technical standards. ## The sources that decide a dispute between private parties The tables above are administrative law and technical standards. A dispute between neighbours is not decided by those. | Source | Subject | Conditions | |---|---|---| | **[Article 844 of the Civil Code](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:regio.decreto:1942-03-16;262)** | Emissions (immissioni) | An owner cannot prevent emissions — smoke, heat, exhalations, **noise, vibration** and similar propagations — from the neighbouring property **if they do not exceed normal tolerability**, having regard also to the condition of the locality. The judge must reconcile the needs of production with the rights of property | | **[Article 659 of the Criminal Code](https://www.normattiva.it/uri-res/N2Ls?urn:nir:stato:regio.decreto:1930-10-19;1398)** | Disturbance of the occupations or rest of persons | It sanctions both producing disturbing noise and failing to prevent animal noise. **It requires the potential to disturb an INDETERMINATE plurality of persons**: if in a condominium the disturbance affects a limited number of residents, it remains a civil matter between neighbours and does not injure the public tranquillity the provision protects. Penalty: arrest up to three months or a fine up to 309 euro | Three consequences that change a technical report. **Normal tolerability is not a numerical threshold.** Article 844 sets no decibels: the judge sets the limit in the specific case, "having regard also to the condition of the locality". The administrative differential criterion can be adopted as a parameter, but it is not one by law — and exceeding an administrative limit does not by itself decide the civil case, just as meeting it does not rule it out. **The condition of the locality enters the judgement.** The same level can be tolerable in an industrial area and not in a residential one, and this does not follow from the municipal acoustic class but from the judge's assessment. **The line between civil and criminal is the audience, not the level.** A very high noise disturbing two flats stays a civil matter; a lower noise capable of disturbing an indeterminate number of people may fall under Article 659. A report intended for criminal proceedings has to document the **spread**, not only the level. ## Interpretative sources These are not standards, and must not be cited as such. They tell you how the administration reads a rule when the text is ambiguous. | Source | What it is | How it is used | |---|---|---| | **[Circulars and opinions of the Ministry of the Environment](https://www.mase.gov.it/)** | Interpretative acts on Law 447/95 and its implementing decrees | They guide the work of enforcement bodies. They create no new obligations and do not bind the judge, but a report departing from them had better say why | | **[Interpelli](https://www.lavoro.gov.it/documenti-e-norme/interpelli/Pagine/default)** (Article 12, Legislative Decree 81/08) | Official answers to interpretation queries on health and safety at work | Relevant to Title VIII: worker noise and vibration. They constitute an interpretative criterion for enforcement activity | | **[Case law](https://www.italgiure.giustizia.it/sncass/)** | Judgments of merit and of the Court of Cassation | It is the source that in practice defines the normal tolerability of Article 844. Cite it in full — division, number, year — or not at all | **Practical rule.** In a report the three categories must be kept separate and qualified: a binding rule, a voluntary technical standard and a ministerial opinion carry three different weights, and presenting them in a row without distinguishing them is the first thing an opposing party attacks. ## Technical standards invoked by a statute A UNI, ISO or IEC standard is voluntary: it binds whoever adopted it by contract or chose to declare conformity to it. It becomes binding on everyone when a statute invokes it — and then **the edition the statute names** applies, not the current one. The issuing body may have withdrawn and replaced it twenty years ago: for the decree it still exists, and on a measurement headed for litigation that is the one that applies. | Binding source | Standard invoked, as named in the text | Status at the issuing body | |---|---|---| | **[Ministerial Decree 16/03/1998](https://www.gazzettaufficiale.it/eli/id/1998/04/01/098A2679/sg)** Art. 2 — measuring system | **EN 60651/1994** and **EN 60804/1994**, required in **class 1** | Withdrawn: the subject moved to the **IEC 61672** series (61672-1:2013, edition 2.0). The decree still names the two EN documents | | **[Ministerial Decree 16/03/1998](https://www.gazzettaufficiale.it/eli/id/1998/04/01/098A2679/sg)** Art. 2 — filters | **EN 61260/1995** | Superseded by **IEC 61260-1:2014**, which split the standard into three parts | | **[Ministerial Decree 16/03/1998](https://www.gazzettaufficiale.it/eli/id/1998/04/01/098A2679/sg)** Art. 2 — microphones | **EN 61094-1/1994**, **-2/1993**, **-3/1995**, **-4/1995** | The series has been revised several times since those dates | | **[Ministerial Decree 16/03/1998](https://www.gazzettaufficiale.it/eli/id/1998/04/01/098A2679/sg)** Art. 2 — calibrators | **CEI 29-4** and, for class 1 periodic verification, **IEC 942:1988** | IEC 942 became **IEC 60942**, now edition 4.0 (2017) | | **[DPCM 05/12/1997](https://www.gazzettaufficiale.it/eli/id/1997/12/22/97A10190/sg)** — single-number ratings | **UNI 8270:1987 Part 7**, §5.1 for R'w and D2m,nT,w, §5.2 for L'n,w | Superseded by **UNI EN ISO 717-1** and **-2**, which are the standards used to compute them today | | **[DPCM 215 of 16/04/1999](https://www.gazzettaufficiale.it/eli/id/1999/07/02/099G0206/sg)** Art. 2 — instrumentation | **EN 60651/1994** and **EN 60804/1994**, class 1 | As for Ministerial Decree 16/03/1998 | In practice the instrument used conforms to IEC 61672-1 and not to EN 60651, which has not been on the market for years. The report settles this in two lines: which standard the decree prescribes, which standard the instrument used meets, and why the second covers the first. It is the first thing an opposing party attacks, and it is closed before the question is put. The converse holds equally: a **new** standard does not enter a decree by virtue of having been published. UNI 11367 has existed since 2010, and since 2023 in a second edition, but it is not a legal requirement — it becomes one where a specification or a CAM invokes it. ## UNI standards | Standard | Subject | Notes on scope | |---|---|---| | **[UNI 11367:2023](https://store.uni.com/uni-11367-2023)** | Acoustic classification of dwelling units | In force since 26 January 2023, replacing UNI 11367:2010. Four classes, from I (best) to IV. **How to read them**: class IV denotes performance that does NOT meet DPCM 5/12/1997, class III corresponds to the decree’s minimum compliance — so "class II" means better than the statutory minimum, not "compliant". Assessment and verification procedures are **in situ**. Annex A carries reference values for hospitals and schools | | **[UNI 11532-1:2018](https://store.uni.com/uni-11532-1-2018)** | Internal acoustic characteristics of confined spaces — general requirements | Descriptors of a room's acoustic quality, reference values by intended use, prediction methods and evaluation techniques common to all sectors | | **[UNI 11532-2:2020](https://store.uni.com/p/UNI1603377/uni-11532-2-2020/UNI1603377)** | Internal acoustic characteristics — school sector | With corrigenda EC1:2020 and EC2:2023. Requirements on reverberation time and speech intelligibility in teaching spaces. It is the part invoked by the CAM for school building procurement | | **[UNI 11532-3](https://store.uni.com/search?q=11532)** | Internal acoustic characteristics — offices, tertiary and collective spaces | **Under development** in the UNI working group: it extends to other sectors the internal acoustic comfort criteria that Part 2 sets for schools. It covers the spaces the earlier parts do not — offices, tertiary and retail spaces, dwellings — and focuses on **reverberation time** and **speech privacy**. Objective: sound absorption parameters and limits on voice disturbance and internal noise for office, retail and **open-plan** buildings. It is a project, and is to be cited as one: it cannot be invoked in a specification | | **[UNI ISO 22955:2023](https://store.uni.com/uni-iso-22955-2023)** | Acoustic quality of open-plan offices | Adoption of ISO 22955. Six open-plan configurations by type of activity, with the performance expected of each. **It is the published reference for open-plan offices** while UNI 11532-3 remains a project | | **[UNI ISO 23591:2023](https://store.uni.com/uni-iso-23591-2023)** | Acoustic quality criteria for music rehearsal rooms and spaces | Adoption of ISO 23591. Acoustic and geometric requirements — volume, height, surfaces — for three categories of music: amplified, low-volume acoustic, high-volume acoustic | | **[UNI 9614:2017](https://store.uni.com/uni-9614-2017)** | Measurement and assessment of vibration in buildings — disturbance to people | Adopts the approach of the Norwegian standard NS 8176 and refers to ISO 2631-2:2003 for measurement methods. It **expressly excludes** seismic vibration, structural damage, occupational hygiene and damage to equipment | | **[UNI 9916:2014](https://store.uni.com/uni-9916-2014)** | Criteria for measuring and assessing the effects of vibration on buildings | Structural response and architectural integrity. It is the **damage** standard, not the disturbance one: the two quantities and the two thresholds are different and sit on scales far apart | ## ISO standards: environmental and outdoor acoustics | Standard | Subject | Scope and limits | |---|---|---| | **[ISO 1996-1:2016](https://www.iso.org/standard/59765.html)** | Description, measurement and assessment of environmental noise — basic quantities | Reconfirmed in 2021. Defines the descriptive quantities and assessment procedures, including guidance on predicting long-term community annoyance response | | **[ISO 1996-2:2017](https://www.iso.org/standard/59766.html)** | Determination of sound pressure levels | Direct measurement and extrapolation by calculation. Intended primarily for outdoors, with some guidance for indoors; applies to every kind of environmental source — road, rail, aircraft, industry | | **[ISO 9613-1:1993](https://www.iso.org/standard/17426.html)** | Attenuation of sound during propagation outdoors — atmospheric absorption | The air absorption coefficient as a function of frequency, temperature and relative humidity; **reconfirmed in 2026**, so in force despite the date. It is the part invoked by Part 2 for the Aatm term | | **[ISO 9613-2:2024](https://www.iso.org/standard/74047.html)** | Engineering method for the prediction of sound pressure levels outdoors | **Edition 2**, published 23 January 2024, reconfirmed in 2025. Cancels and replaces the 1996 edition, whose title was *General method of calculation*. Algorithms in **octave bands** with nominal centre frequencies from 63 Hz to 8 kHz, for a point source or an assembly of point sources | | **[ISO 3744:2025](https://www.iso.org/standard/80866.html)** | Determination of sound power levels from sound pressure, in an essentially free field over a reflecting plane | **Edition 4**, December 2025, replacing 2010. The new edition **no longer covers** the determination of sound energy level, removed for lack of use, and moves part of the test-environment qualification into ISO 26101-2. Adopted in Italy as **UNI EN ISO 3744:2026** (April 2026): a report should cite the adoption | ## ISO standards: room and building acoustics | Standard | Subject | Scope and limits | |---|---|---| | **[ISO 3382-1:2009](https://www.iso.org/standard/40979.html)** | Measurement of room acoustic parameters — performance spaces | Reconfirmed in 2021. Clarity, definition and early decay time parameters, measured from an impulse response | | **[ISO 3382-2:2008](https://www.iso.org/standard/36201.html)** | Measurement of reverberation time in ordinary rooms | Reconfirmed in 2022. Three accuracy grades — survey, engineering, precision — with different requirements on the number of positions and repetitions | | **[ISO 354:2003](https://www.iso.org/standard/34545.html)** | Measurement of sound absorption in a reverberation room | **Edition 2**, reconfirmed in 2024 and therefore in force — but **currently under revision**, and the stated reason is inter-laboratory reproducibility. In round-robin comparisons the reproducibility limit of α reaches **0.7 at 125 Hz** and stays above 0.2 even at 5 kHz | | **[ISO 717-1:2020](https://www.iso.org/standard/77435.html)** | Rating of sound insulation — airborne sound | Rules for deriving single-number quantities from band measurements, and for simplifying the formulation of requirements in building codes | | **[ISO 717-2:2020](https://www.iso.org/standard/69867.html)** | Rating of sound insulation — impact sound | Single-number quantities for the impact sound reduction of floor coverings and floating floors | | **[ISO 12354-1:2017](https://www.iso.org/standard/70242.html)** | Estimation of building acoustic performance from element performance — airborne insulation | Calculation models for insulation between adjacent rooms from measured element data, with direct and flanking transmission. The detailed model works in **one-third-octave bands from 100 to 3150 Hz**, consistently with ISO 717-1 | | **[ISO 12354-2:2017](https://www.iso.org/standard/70243.html)** | Estimation of performance — impact sound insulation | Second part of the prediction series | | **[ISO 12354-3:2017](https://www.iso.org/standard/70244.html)** | Estimation of performance — façade insulation against outdoor noise | Third part | | **[ISO 12354-4:2017](https://www.iso.org/standard/70248.html)** | Estimation of performance — transmission of indoor sound to the outside | Fourth part | | **[ISO 10140-1:2016](https://www.iso.org/standard/67232.html)** | LABORATORY sound insulation — application rules for specific products | Preparation, mounting and test conditions for each product family: it is the part that decides whether two datasheets are comparable | | **[ISO 10140-2:2021](https://www.iso.org/standard/79487.html)** | LABORATORY sound insulation — airborne | **Edition 2** | | **[ISO 10140-3:2021](https://www.iso.org/standard/79483.html)** | LABORATORY sound insulation — impact sound | **Edition 2** | | **[ISO 10140-4:2021](https://www.iso.org/standard/73911.html)** | LABORATORY sound insulation — measurement procedures and requirements | **Edition 2** | | **[ISO 10140-5:2021](https://www.iso.org/standard/79482.html)** | LABORATORY sound insulation — requirements for test facilities and equipment | **Edition 2**. With Part 4 it is what makes the result repeatable across laboratories | | **[ISO 16283-1:2014 + Amd 1:2017](https://www.iso.org/standard/55997.html)** | Field measurement of sound insulation — airborne sound | Field measurement procedures, distinct from the laboratory procedures of the ISO 10140 series. In Europe the applied document is **EN ISO 16283-1:2014+A1:2017**, adopted in Italy as **UNI EN ISO 16283-1:2018**: citing 2014 alone omits the amendment. Volumes from 10 to 250 m³, 50–5000 Hz | | **[ISO 16283-2:2020](https://www.iso.org/standard/77436.html)** | Field measurement — impact sound insulation | Second part of the field series, for impact sound. A revision is under way (ISO/DIS 16283-2, ed. 3) | | **[ISO 16283-3:2016](https://www.iso.org/standard/59748.html)** | Field measurement — façade sound insulation | Element methods and global methods on the whole façade, from sound pressure measurements | | **[ISO 3382-3:2022](https://www.iso.org/standard/77437.html)** | Room acoustic parameters — open-plan offices | **Edition 2**, replacing the 2012 edition with a technical revision. It introduces the quantities specific to open-plan spaces (distraction distance, spatial decay of speech), which are not those of a hall | ## ISO standards: vibration | Standard | Subject | Scope and limits | |---|---|---| | **[ISO 2631-1:1997 + Amd 1:2010](https://www.iso.org/standard/7612.html)** | Evaluation of human exposure to whole-body vibration — general requirements | Direction-dependent frequency weightings: the response along the vertical axis differs from that along the horizontal axes. **Note**: a revision is under way (ISO/DIS 2631-1), so the edition may change shortly | | **[ISO 2631-2:2003](https://www.iso.org/standard/23012.html)** | Vibration in buildings, 1 to 80 Hz | This is the part invoked by UNI 9614:2017 for measurement methods | | **[ISO 5349-1:2001](https://www.iso.org/standard/32355.html)** | Hand-transmitted vibration — general requirements | **Reconfirmed in 2026**, so in force. It is the standard behind the hand-arm A(8) value of Legislative Decree 81/08: without it that figure has no method | | **[ISO 5349-2:2001 + Amd 1:2015](https://www.iso.org/standard/27511.html)** | Hand-transmitted vibration — practical workplace guidance | The operational part: where the accelerometer goes, how the grip is handled, how the working day is composed | | **[EN ISO 5349-3:2025](https://www.iso.org/standard/83792.html)** | Hand-transmitted vibration — shock | **New part**, on shocks transmitted to the hand: a case not covered by Parts 1 and 2, which assume continuous vibration | ## IEC standards: instrumentation | Standard | Subject | Scope and limits | |---|---|---| | **[IEC 61672-1:2013](https://webstore.iec.ch/en/publication/5708)** | Sound level meters — specifications | **Edition 2.0**. Two performance classes, 1 and 2, with the same design goals and different acceptance limits: at the 1 kHz reference frequency the tolerance is ±1.1 dB for class 1 and ±1.4 dB for class 2. Covers time-weighting, integrating-averaging and sound-exposure meters | | **[IEC 61672-2:2013](https://webstore.iec.ch/en/publication/5709)** | Sound level meters — pattern evaluation tests | The tests a MODEL of instrument must pass for approval. It is the standard cited on the approval certificate, not on the calibration one | | **[IEC 61672-3:2013](https://webstore.iec.ch/en/publication/5710)** | Sound level meters — periodic tests | The tests on the INDIVIDUAL unit, those of periodic verification. A meter "conforming to IEC 61672-1" without periodic verification per Part 3 has no conformity demonstrated over time | | **[IEC 61260-1:2014](https://webstore.iec.ch/en/publication/5063)** | Octave-band and fractional-octave-band filters | Performance requirements for analogue, sampled-data and digital implementations. It is the standard that defines what may be called an "octave band" or a "one-third-octave band" | | **[IEC 61260-2:2016](https://webstore.iec.ch/en/publication/24398)** | Band filters — pattern evaluation tests | As 61672-2, but for filters | | **[IEC 61260-3:2016](https://webstore.iec.ch/en/publication/24399)** | Band filters — periodic tests | **Edition 1.0**. Periodic tests on filters designed for class 1 or class 2 of IEC 61260-1:2014: it is the check on the unit, not on the model | | **[IEC 60942:2017](https://webstore.iec.ch/en/publication/30045)** | Sound calibrators | **Edition 4.0**. Three classes: **LS** (laboratory standard), **1** and **2** for field use, with acceptance limits widening in that order. It is the device used to check the meter before and after each session: its class enters the measurement uncertainty budget | | **[IEC 61252:2025](https://webstore.iec.ch/en/publication/68929)** | Personal sound exposure meters | **New edition**: it replaces the 1993 edition with its Amd 1:2000 and Amd 2:2017, which circulated as the consolidated `1993+AMD1+AMD2` version. It measures A-weighted sound exposure from steady, intermittent, fluctuating, irregular or impulsive sound, in **a single accuracy grade** — there are no class 1 and class 2 as for sound level meters | | **[IEC 60268-16:2020](https://webstore.iec.ch/en/publication/26771)** | Objective rating of speech intelligibility — STI | **Edition 5.0**, replacing edition 4 (2011). A matrix of **7 octave bands** (125 Hz – 8 kHz) by **14 modulation frequencies** (0.63 to 12.5 Hz), that is 98 modulation transfer values. Edition 5 changed the male test-signal spectrum, with significant reductions in the 125 and 250 Hz bands | **Why the three parts matter.** A datasheet declaring "conforms to IEC 61672-1 class 1" says what the instrument should do. Part **-2** is the standard under which that model was approved; part **-3** is the one under which the individual unit is periodically verified. A measurement headed for a dispute needs all three: the calibration certificate, the class of the field calibrator used, and the date of the last periodic verification. ### The meter class enters the uncertainty budget The difference between class 1 and class 2 is not accuracy "in general": it is different acceptance limits and different operating temperature ranges. On a measurement that has to be compared with a statutory threshold, that difference enters the uncertainty budget — and a 1 dB margin against the limit does not survive an instrument with a ±1.4 dB tolerance at the reference frequency. It is why Ministerial Decree 16/03/1998 prescribes the class. ## Uncertainty and the conformity decision | Standard | Subject | Notes | |---|---|---| | **[ISO 14253-1](https://www.iso.org/standard/70137.html)** | Decision rules for proving conformity or nonconformity | It originates in geometrical product specification, but the rule is general: it defines the **guard bands** by which an outcome is decided when the measured value sits close to the limit and the uncertainty is not negligible | This is the standard most often missing from an acoustic report. A value of 54.8 dB(A) against a 55 limit is not "conforming" if the expanded uncertainty is ±1.5 dB: without a stated decision rule, that outcome is an unmotivated choice. The page on [measurement uncertainty](/en/wiki/measurement-uncertainty/) covers the budget; what matters here is the step after it — how a budget becomes a judgement. ## Other European national systems | Standard | Subject | Notes | |---|---|---| | **[BS 5228-1:2009+A1:2014](https://knowledge.bsigroup.com/products/code-of-practice-for-noise-and-vibration-control-on-construction-and-open-sites-noise)** | Noise on construction and open sites | The British code of practice, used as an international reference for construction-noise prediction well beyond the UK. A1:2014 supersedes the 2009 edition, which is withdrawn | | **[BS 5228-2:2009+A1:2014](https://knowledge.bsigroup.com/products/code-of-practice-for-noise-and-vibration-control-on-construction-and-open-sites-vibration)** | Vibration on construction and open sites | The companion part on vibration, with the reference thresholds for damage and for disturbance during construction | | **[NF S 31-010:1996](https://norminfo.afnor.org/norme/pr-nf-s31-010/acoustique-caracterisation-et-mesurage-des-bruits-de-lenvironnement-methodes-particulieres-de-mesurage/105084)** | Characterisation and measurement of environmental noise | December 1996, with amendment **A1** on meteorological data. French method standard, invoked by the French regulations on neighbourhood noise. A revision is under way at AFNOR: the link is to the project record | | **[NF S 31-057:1982](https://cnejac.org/wp-content/uploads/2018/01/NF_S_31-057.pdf)** | Verification of the acoustic quality of buildings | October 1982. **Withdrawn by AFNOR** and used regardless: it is the acoustic commissioning reference in French expert reports, and the text stays distributed by CNEJAC for that use. The case shows that "withdrawn" does not mean "not applied" | Vibration in construction has a German reference that circulates as a de facto standard well outside Germany: it is in the DIN table below, with the rest of the series. ## Standards outside Italy and outside ISO/IEC Needed when the client, the product or the datasheet comes from outside Europe. **The American quantities are not translations of the ISO ones**: STC, IIC and NRC are defined by their own methods, and treating them as synonyms of Rw, Ln,w and αw produces comparisons that do not survive scrutiny. ### United States — ANSI / ASA | Standard | Subject | Notes | |---|---|---| | **[ANSI/ASA S12.60/Part 1-2010 (R2020)](https://webstore.ansi.org/standards/asa/ansiasas1260part2010r2020)** | School acoustics — permanent schools | Performance criteria and design requirements: for an unoccupied, furnished classroom under 283 m³ (10,000 ft³) it sets a **maximum T60 of 0.6 s** and a **maximum background noise of 35 dB(A)** | | **[ASA/ANSI S12.60-2019/Part 4 (R2024)](https://webstore.ansi.org/standards/asa/ansiasas12602019part)** | School acoustics — gyms and physical-education spaces | A dedicated part: sports spaces have volumes and requirements different from a classroom | | **[ANSI/ASA S1.4-2014/Part 1](https://webstore.ansi.org/standards/asa/asaansis12014partiec616722013)** | Sound level meters — specifications | The national adoption of **IEC 61672-1:2013**: same technical content, different designation | | **[ANSI/ASA S1.11-2014/Part 1](https://webstore.ansi.org/standards/asa/ansiasas1112014partiec61260)** | Octave-band and fractional-octave-band filters | National adoption of **IEC 61260-1:2014** | | **[ASA/ANSI S12.54-2011 (R2025)](https://webstore.ansi.org/standards/asa/ansiasas12542011iso37442010)** | Sound power levels in an essentially free field over a reflecting plane | National adoption of **ISO 3744:2010** — so the ISO 2025 edition is not yet adopted: work to an American specification may land on the 2010 edition | | **[ASA/ANSI S2.72-2002/Part 1 (R2023)](https://webstore.ansi.org/standards/asa/asaansis2722002partiso26311997-2502283)** | Human exposure to whole-body vibration | National adoption of **ISO 2631-1:1997 + Amd 1:2010** | ### United States — ASTM | Standard | Subject | Notes | |---|---|---| | **[ASTM E90](https://www.astm.org/standards/e90)** | Laboratory airborne sound insulation | Test method; the single-number rating is assigned by E413. The usual phrasing is "tested per ASTM E90, rated per ASTM E413" | | **[ASTM E413-22](https://www.astm.org/standards/e413)** | Classification: **STC** (Sound Transmission Class) | Over **16 one-third-octave bands from 125 to 4000 Hz**. It is not Rw: the band range and the reference curve differ | | **[ASTM E336](https://www.astm.org/standards/e336)** | Field airborne sound insulation | Single-number ratings: NIC, NNIC and **ASTC** (Apparent STC), which includes flanking transmission. In the current editions of E336 and E413 the standard field rating is ASTC | | **[ASTM E492](https://www.astm.org/standards/e492)** | Laboratory impact sound | From which **E989-21** assigns the **IIC** (Impact Insulation Class) | | **[ASTM E1007](https://www.astm.org/standards/e1007)** | Field impact sound | Field metrics AIIC, ISR and NISR, assigned by E989-21 | | **[ASTM C423](https://www.astm.org/standards/c423)** | Sound absorption by the reverberation room method | The American counterpart to **ISO 354**, and the two do not return the same figures: the literature on the deviations between the two methods exists and is documented | ### Germany — DIN / VDI | Standard | Subject | Notes | |---|---|---| | **[DIN 4109-1:2018-01](https://www.baunormenlexikon.de/norm/din-4109-1/eb4eb6d4-77f8-42b0-8939-f5c6fc714a88)** | Sound insulation in buildings — minimum requirements | January 2018. Requirements on component insulation and on permitted levels in *schutzbedürftige Räume*, the rooms to be protected. It is the functional equivalent of our DPCM 5/12/1997, with requirements and verifications of its own | | **[DIN 18041:2016](https://www.baunormenlexikon.de/norm/din-18041/8047ccbe-c76f-4ce0-b94b-e92a51495ed5)** | Acoustic quality in enclosed spaces | *Hörsamkeit in Räumen*: recommended reverberation times by intended use, with verbal communication as the stated objective. Functional equivalent of the UNI 11532 series | | **[DIN 4150-2:1999-06](https://www.dinmedia.de/en/standard/din-4150-2/12168614)** | Vibration in construction — effects on people in buildings | June 1999. The German counterpart of UNI 9614: it is the **annoyance** standard | | **[DIN 4150-3:2016-12](https://www.baunormenlexikon.de/norm/din-4150-3/2fb00265-fe7d-460e-a9bb-3016d47dc3c0)** | Vibration in construction — effects on structures | December 2016, replacing 1999-02. It is the **damage** standard, and the more cited of the two outside Germany: it turns up in site prescriptions even where the applicable standard would be UNI 9916 | | **[VDI 2058 Blatt 2](https://www.vdi.de/mitgliedschaft/vdi-richtlinien/details/vdi-2058-blatt-2-beurteilung-von-laerm-hinsichtlich-gehoergefaehrdung)** | Noise and the risk of hearing damage | Revised **2020-08** | | **[VDI 2058 Blatt 3](https://www.vdi.de/richtlinien/details/vdi-2058-blatt-3-assessment-of-noise-in-the-working-area-with-regard-to-specific-operations)** | Workplace noise for specific operations | Edition **2014-08**, invoked by the *Arbeitsstättenverordnung* for workplace immission limits | | **[VDI 2569](https://www.vdi.de/richtlinien/details/vdi-2569-schallschutz-und-akustische-gestaltung-in-bueros)** | Noise protection and acoustic design in offices | The German reference for open-plan offices, where UNI 11532-1 covers the case more generally | **A caution on comparing systems.** National adoptions can sit on an earlier ISO edition: ASA/ANSI S12.54 adopts ISO 3744 **in its 2010 version**, not the 2025 one. On a job citing an American designation, check which ISO edition it corresponds to, because it need not be the one in force in Europe. ## What changed in the edition in force Only for editions published from 2011 on, that is less than fifteen years old. For the others — ISO 354:2003, ISO 3382-1:2009 and -2:2008, ISO 9613-1:1993, and the Italian statutes of the 1990s — whoever uses them has been working with that version for over a decade, and the change history adds nothing operational. It serves one concrete purpose: re-reading earlier work. If a report was produced under the previous edition, these lines say whether the two results are comparable or not. **ISO 9613-2:2024** (ed. 2, January 2024) replaces the 1996 edition. The title changes from *General method of calculation* to *engineering method for the prediction of sound pressure levels*, and the rewrite concerns §7.4: the formulation of barrier diffraction loss changes, and so does the meteorological correction. **Two reports citing "ISO 9613-2" without an edition may have used two different methods.** That rewrite now has amendment **ISO 9613-2:2024/DAmd 1** out for DIS ballot, restoring both formulas to their 1996 form, while the ISO catalogue already carries the **third edition** in drafting, marked "will replace ISO 9613-2:2024": [what changes, and by how much](/en/blog/iso-9613-2-amd1-cosa-cambia/). **ISO 3744:2025** (ed. 4, December 2025) replaces the 2010 edition. The new edition **removes** the determination of sound energy level, for lack of use, and moves part of the test-environment qualification into ISO 26101-2; it clarifies cylindrical-surface measurements and adds Annex I on reducing uncertainty. The core measurement procedure and the standard deviation of reproducibility of the main procedure are unchanged, so results obtained under the 2010 edition remain comparable. **ISO 1996-1:2016** (ed. 3) replaces the 2003 edition with a technical revision: subclauses 3.6, 6.3.1, 6.5, 8.1, 8.2.1 i) and Annexes A, D, E, F, G, H were added or revised. **ISO 1996-2:2017** (ed. 3) replaces the 2007 edition with a technical revision. The change that bears on daily use is the **residual sound** parameter, defined as all sound not belonging to the specific source under investigation — a quantity distinct from the background noise level L_N. Anyone comparing a 2010 measurement with a current one has to check which of the two was used. **ISO 717-1:2020** replaces the 2013 edition. The changes are organisational: Annex G.6 was relocated from ISO 10140, as were the smoothed reference spectra of the sound reduction index of basic elements (from Annex B of ISO 10140-5:2018); references updated. **ISO 717-2:2020** replaces the 2013 edition and adds a **new Annex D**, with a method for rating heavy/soft impact sound insulation based on the A-weighted maximum impact sound pressure level. **ISO 12354-1:2017** is the ISO adoption of EN 12354-1:2000, which it replaces. The detailed model of ISO 12354-1 works in one-third-octave bands from 100 to 3150 Hz per ISO 717-1, extendable down to 50 Hz where element and junction data allow. **ISO 16283-1:2014** replaces ISO 140-4 for field measurements, and has an **Amd 1:2017**: the document applied in Europe is **EN ISO 16283-1:2014+A1:2017**, and citing 2014 alone omits the amendment. It covers volumes from 10 to 250 m³ over the 50 to 5000 Hz range. **IEC 61672-1:2013** (ed. 2.0) replaces the 2002 edition, and the change is in the conformance criterion. In the first edition conformance required the measured deviation **extended by the uncertainty** to fall within the tolerance limits; in the second it requires the measured deviation not to exceed the acceptance limits **and** the measurement uncertainty not to exceed the maximum permitted, both at a 95 % coverage probability. This is not a trim: two instruments judged conforming under the two editions need not be the same set. **IEC 61260-1:2014** replaces IEC 61260:1995 and its Amd 1:2001, and splits the single document into three parts (specifications, pattern evaluation tests, periodic tests). Technical changes that matter: performance **class 0 was removed**, design goals may be base-10 only, the reference environmental conditions move from 20 °C / 65 % RH to **23 °C / 50 % RH**, and tolerance limits now account for measurement uncertainty, which the 1995 edition did not consider. **IEC 60268-16:2020** (ed. 5.0) replaces the 2011 edition. It changed the **male test-signal spectrum**, with significant reductions in the 125 and 250 Hz bands. An STI value measured under the fourth edition and one measured under the fifth are not directly comparable. **UNI 11367:2023** replaces UNI 11367:2010, with a revision of the normative references and an update to some clauses. The framework — four classes from I to IV, in-situ assessment — is unchanged. **UNI 11532-1:2018** and **UNI 11532-2:2020** turned UNI 11532 from a single standard into a **series**: Part 1 carries the general requirements common to all sectors, Part 2 the education sector. Part 2 has two corrigenda, EC1:2020 and EC2:2023. **UNI 9614:2017** replaces the 2004 edition and is not a cosmetic update: it introduces a different assessment approach, taken from the Norwegian standard **NS 8176**, and refers to ISO 2631-2:2003 for measurement methods. **A 2010 report and a 2020 one are not comparable by default.** **UNI 9916:2014** replaces the 2004 edition (in force since 16 January 2014). It classifies structures into fourteen categories and considers the frequency range from 0.1 to 150 Hz. **Legislative Decree 42/2017** replaced the regime in which recognition of the qualified technician was regional: it establishes the **national register** at the Ministry of the Environment, fed by the Regions and published through ISPRA, and introduces **mandatory continuing education** — at least 30 hours every five years, over a minimum of three. Those recognised under the previous regime carried over into the register; the training obligation, by contrast, is new. **Ministerial Decree 24/11/2025** (building CAM) replaces Decree 256/2022 and the corrective Decree of 5 August 2024, in force since 1 February 2026. The framework is aligned to the 2023 Public Contracts Code, with changes on design, construction products, waste management, ESG criteria and site personnel. ## How to cite a standard in a report Three points an opposing party checks first. **Write the edition.** "Per ISO 9613-2" does not identify a method: between the 1996 and the 2024 editions the formulation of barrier diffraction changed, so two reports citing the same standard without an edition may have used two different methods. The same holds for UNI 9614, where the 2017 edition introduced an assessment approach different from its predecessor. **State the basis on which a voluntary standard applies.** A contract, a local regulation, or a criterion adopted by a court: three different things, and an opposing party's first question is which of the three. **Scope bounds what the standard can conclude.** UNI 9614 excludes structural damage, so it does not support the conclusion that a building is undamaged. Symmetrically, UNI 9916 says nothing about disturbance to people. ## Limits of this page - **It carries the references, not the text of the standards.** Limit values, formulas and procedures live in the original documents — paywalled for technical standards, in the Official Gazette for statutes and decrees. - **It does not cover** machinery acoustics (the Machinery Directive and its dedicated ISO series), forensic acoustics, construction-product certification, or occupational exposure beyond the reference to Legislative Decree 81/08. - **Outside Italy** it covers ANSI/ASA, ASTM, DIN, VDI and the two construction BS documents, the systems most often met on a job. It does not cover the rest of the BS catalogue beyond the EN adoptions, nor the Japanese (JIS), Chinese (GB) or Australian/New Zealand (AS/NZS) systems. - **It does not replace an opinion.** Establishing which standard applies to a specific case, and on what basis, is precisely the activity reserved to the qualified technician. ## References Italian legal texts: [Normattiva](https://www.normattiva.it/) (text in force) and [Gazzetta Ufficiale](https://www.gazzettaufficiale.it/) (text as published). National register of qualified acoustics technicians: [ENTECA — ISPRA](https://www.mase.gov.it/portale/elenco-nazionale-dei-tecnici-competenti-in-acustica-ex-art-21-d-lgs-17-febbraio-2017-n-42). Technical standard catalogues: [ISO](https://www.iso.org/), [IEC](https://webstore.iec.ch/), [UNI](https://store.uni.com/). Progress of Italian standards projects: [UNI](https://www.uni.com/) and [ANIT](https://www.anit.it/), which publishes technical updates on drafts in preparation — that is how to follow UNI 11532-3. The figure on the inter-laboratory reproducibility of ISO 354 comes from the literature supporting the revision of the standard (round-robin comparisons between laboratories). Related pages on this site: [differential criterion](/en/wiki/criterio-differenziale/), [road noise limits](/en/wiki/italian-road-noise-limits/), [reverberation time](/en/wiki/reverberation-time/), [vibration in buildings](/en/wiki/vibrazioni-edifici/), [LEX,8h](/en/wiki/lex-8h/).