{"id":21762,"date":"2025-08-04T13:54:05","date_gmt":"2025-08-04T12:54:05","guid":{"rendered":"https:\/\/www.serianaedilizia.it\/?p=21762"},"modified":"2025-09-04T15:54:31","modified_gmt":"2025-09-04T14:54:31","slug":"seveso-natech-why-seismic-retrofit-is-strategic-for-major-accident-hazard-mah-establishments","status":"publish","type":"post","link":"https:\/\/www.serianaedilizia.it\/en\/seveso-natech-why-seismic-retrofit-is-strategic-for-major-accident-hazard-mah-establishments\/","title":{"rendered":"Seveso &amp; NaTech: why seismic retrofit is strategic for Major-Accident Hazard (MAH) establishments"},"content":{"rendered":"\n<p>At sites governed by the Seveso Directive\u2014classified in Italy as <em>Rischio di Incidente Rilevante<\/em> (RIR, i.e. Major-Accident Hazard establishments)\u2014seismic strengthening is not merely a \u201cnice-to-have\u201d, but a statutory duty. The combination of hazardous substances, a high concentration of personnel and the potential for explosions or toxic releases\u2014together with earthquake exposure\u2014demands targeted structural interventions.<\/p>\n\n\n\n<p>Upgrading plant structures means:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Preventing environmental disasters and safeguarding the health of workers and neighbouring communities.<\/strong><\/li>\n\n\n\n<li><strong>Maintaining operational continuity after an earthquake, minimising damage and downtime.<\/strong><\/li>\n\n\n\n<li><strong>Achieving full compliance with Seveso obligations and NaTech guidelines, thereby avoiding penalties and protecting corporate reputation.<\/strong><\/li>\n<\/ul>\n\n\n\n<p><strong>Legislative framework: Italian Legislative Decree 105\/2015 (Seveso III)<\/strong><\/p>\n\n\n\n<p>Legislative Decree 105\/2015\u2014implementing Directive 2012\/18\/EU\u2014aims to prevent major accidents involving dangerous substances and to limit their consequences for:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Human health<\/strong><\/li>\n\n\n\n<li><strong>The environment<\/strong><\/li>\n\n\n\n<li><strong>Material assets<\/strong> (including cultural heritage and infrastructure)<\/li>\n<\/ul>\n\n\n\n<p>Industrial establishments subject to Legislative Decree 105\/2015 handle hazardous substances in quantities that can generate major accidents. In Italy, these sites fall into Use Class IV under the 2018 Technical Standards for Construction (NTC 2018): they must therefore ensure a higher level of seismic safety than that required for ordinary buildings. The reason is clear: an earthquake can trigger, worsen, or prevent the containment of an accident \u2014 the so-called earthquake-related NaTech risk (Natural Hazards Triggering Technological Disasters). (UNI\/TS 11816-1:2021 standard \u201cGuidelines for the management of NaTech events within establishments with a major-accident hazard\u201d).<\/p>\n\n\n\n<p>In this scenario, seismic retrofitting and upgrading are not mere technical options, but legal obligations and opportunities to protect people, the environment, and business continuity.<\/p>\n\n\n\n<p><strong>Seveso and seismic risk: what the law says<\/strong><br><strong>I. Legislative Decree 105\/2015 (Seveso III legislation)<\/strong><\/p>\n\n\n\n<p><br>Legislative Decree 105\/2015: requires the operator to prevent major accidents and to assess natural events (earthquakes included) in the Safety Report.<br>Legislative Decree 105\/2015, which transposes Directive 2012\/18\/EU on the control of major-accident hazards involving certain dangerous substances, classifies as major-accident hazard (RIR) establishments those plants in which a large-scale release, fire or explosion \u2014 due to uncontrolled developments \u2014 may pose a serious, immediate or delayed danger to human health or the environment, inside or outside the establishment, in the presence of one or more dangerous substances.<br>Legislative Decree 105\/15 requires, for all establishments within its scope, the preparation of a safety analysis which, in identifying hazards and assessing major-accident risks, also takes natural events into account.<\/p>\n\n\n\n<p><strong>Summary of the main definitions in Legislative Decree 105\/2015<\/strong><strong><br><\/strong><\/p>\n\n\n\n<p><strong>Establishment<\/strong> \u2014 The entire area under an operator\u2019s control where dangerous substances are present in one or more installations, including related infrastructure and activities.<\/p>\n\n\n\n<p><strong>Installation<\/strong> \u2014 A technical unit (above or below ground) within the establishment in which dangerous substances are produced, used, handled or stored; includes all equipment and structures needed for its operation (tanks, pipelines, jetties, warehouses, etc.).<\/p>\n\n\n\n<p><strong>Operator <\/strong>\u2014 A natural or legal person who owns\/operates the establishment or installation, or who has delegated decision-making and financial authority for its technical operation.<\/p>\n\n\n\n<p><strong>Major accident<\/strong> \u2014 An event (large-scale release, fire or explosion) due to uncontrolled developments that poses a serious, immediate or delayed danger to human health or the environment, inside or outside the establishment, involving one or more dangerous substances.<\/p>\n\n\n\n<p><strong>Domino effect<\/strong> \u2014 A sequence of major accidents, possibly of different types, that are inter-related and affect installations in one or more establishments, generating direct or indirect, immediate or delayed effects (inter-establishment scenario).<\/p>\n\n\n\n<p><strong>Regional Technical Committee (RTC)<\/strong> \u2014 A collegiate body chaired by the Regional Fire Service Director, composed of technical agencies (Fire Service, ARPA, INAIL, Region, Local Health Authority, etc.), which reviews and approves Safety Reports for upper-tier establishments.<\/p>\n\n\n\n<p><strong>What are the operator\u2019s general duties? (Art. 12)<\/strong><br>The operator must adopt all suitable measures to prevent major accidents and to limit their consequences for human health and the environment. In addition, the operator must be able, at any time, to demonstrate to the competent and supervisory authorities\u2014particularly for the purposes of inspections and audits\u2014the adoption of all measures required by this Legislative Decree.<\/p>\n\n\n\n<p><strong>What to know about the Safety Report? (Art. 15)<\/strong><br>Below is a concise summary of the safety report:<\/p>\n\n\n\n<p><strong>\u2022 Obligation<\/strong><br>The operator of an upper-tier establishment must draft and submit a Safety Report.<\/p>\n\n\n\n<p><strong>\u2022 Purpose of the document<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>Demonstrate the implementation of a major-accident prevention policy and an adequate safety management system.<\/li>\n\n\n\n<li>Describe hazards, risk scenarios, prevention\/mitigation measures, and potential consequences (including off-site).<\/li>\n\n\n\n<li>Provide the authorities with the elements needed for land-use planning and civil protection.<\/li>\n<\/ol>\n\n\n\n<p><strong>\u2022 Timing<\/strong><br>\u2022 New establishments: before start-up.<br>\u2022 Significant modifications: within 12 months.<br>\u2022 Periodic update: at least every 5 years or when substantial changes \/ new data arise.<\/p>\n\n\n\n<p><strong>\u2022 Submission<\/strong><br>The report must be sent to:<br>\u2022 Ministry of the Environment and Energy Security (MASE)<br>\u2022 Regional Technical Committee (CTR)<br>\u2022 Prefect (emergency planning)<br>\u2022 Competent Region and Municipality.<\/p>\n\n\n\n<p><strong>\u2022 Assessment<\/strong><br>The CTR reviews the report, may request additions, carry out inspections, and verify the safety management system. Operations may proceed only after a positive outcome.<\/p>\n\n\n\n<p><strong>\u2022 Annex C<\/strong><br>Provides the technical-engineering criteria to draft\/review the report; among these: precautions and safety factors adopted (including seismic actions) for structures, critical components, and control rooms.<\/p>\n\n\n\n<p><strong>What is the difference between the Operator and the Employer?<\/strong><br>In companies subject to the Seveso legislation, the Operator and the Employer often coincide within the same legal entity, but they fall under two different regulatory frameworks that must be coherently integrated into risk management.<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/lh7-rt.googleusercontent.com\/docsz\/AD_4nXdWvOALTPvKvxm3Fg-OBbxYw6my4CQcXoabdBIcv_RwxSLkY5Qy-Z_h8bWC1BKSAhykzb-_f8mMgnhooAq8Hu_qZJA0wXjpLknojDIa-frWlmANxLNMhMdAc_uJs3rQM6h4vXDRbA?key=0GGjjFYhD_uGPVg1iOhzdA\" alt=\"Immagine che contiene schermata, testo, Carattere, diagramma\n\nDescrizione generata automaticamente\"\/><\/figure>\n\n\n<h1 class=\"wp-block-heading\" id=\"comparative-summary-of-the-two-roles\"><strong>Comparative summary of the two roles<\/strong><\/h1>\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th><strong>Aspect<\/strong><\/th><th><strong>Operator (Seveso)<\/strong><\/th><th><strong>Employer (D.Lgs. 81\/2008)<\/strong><\/th><\/tr><\/thead><tbody><tr><td><strong>Definition<\/strong><\/td><td>The entity that operates or controls a major-accident-hazard installation.<\/td><td>The person who holds the employment relationship or is responsible for the company\u2019s organisation.<\/td><\/tr><tr><td><strong>Reference legislation<\/strong><\/td><td><strong>D.Lgs. 105\/2015<\/strong><\/td><td><strong>D.Lgs. 81\/2008<\/strong><\/td><\/tr><tr><td><strong>Responsibilities<\/strong><\/td><td>Ensure installation safety; prevent major accidents; prepare the <strong>Safety Report<\/strong> and the <strong>Internal Emergency Plan (PEI)<\/strong>.<\/td><td>Ensure workers\u2019 safety; draw up the <strong>Risk Assessment Document (DVR)<\/strong>; <strong>train and inform<\/strong>.<\/td><\/tr><tr><td><strong>Common obligations<\/strong><\/td><td>Major-accident risk assessment; <strong>PEI\/Emergency Plan<\/strong>; notifications\/communications to authorities (public administration, population).<\/td><td>Assessment of <strong>all<\/strong> occupational risks; <strong>appoint the H&amp;S manager (RSPP)<\/strong>; emergency management and occupational health surveillance.<\/td><\/tr><tr><td><strong>Role in NaTech risk<\/strong><\/td><td>Integrate natural hazards into industrial risk analyses (e.g., earthquakes, floods).<\/td><td>Consider external events relevant to workers\u2019 safety.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p><strong>II. O.P.C.M. no. 3274 of 20 March 2003<\/strong><br><strong>What does Art. 2 paragraph 3 say?<\/strong><\/p>\n\n\n\n<p><br>It requires the respective owners to carry out a verification, in accordance with the standards set out in the aforementioned annexes, both for buildings of strategic interest and for infrastructure whose functionality during seismic events is of fundamental importance for civil protection purposes, and for buildings and infrastructure that may be relevant in relation to the consequences of a possible collapse.<\/p>\n\n\n\n<p><strong>III. Consolidated text of Annex 2 \u2013 Buildings \u2013 to Ordinance 3274 as amended by OPCM 3431 of 03\/05\/05<\/strong><strong><br><\/strong><strong>What are the technical rules for the design, assessment and seismic upgrading of buildings?<\/strong><\/p>\n\n\n\n<p><strong><br><\/strong>Structures must be provided with a level of seismic protection differentiated according to their importance and use, and therefore according to the more or less serious consequences of damage caused by an earthquake.<br>For this purpose, different \u201cimportance categories\u201d are established, each associated with a factor \u03b3I, called the importance factor (see Consolidated text of Annex 2 \u2013 Buildings \u2013 to Ordinance 3274 as amended by OPCM 3431 of 3\/5\/05, point 4.7). This factor amplifies the intensity of the design seismic action with respect to the value assumed for ordinary-importance constructions (reference seismic action).<\/p>\n\n\n\n<p><strong>IV. NTC 2018 and Circular No. 7 of 21 January 2019 of the Superior Council of Public Works<\/strong><\/p>\n\n\n\n<p><strong><br><\/strong>Circular No. 7\/2019 of the Superior Council of Public Works provides operational guidance for applying the new 2018 Technical Standards for Construction (Ministerial Decree of 17 January 2018), replacing the previous Circular 617\/2009 linked to the 2008 NTC. The document offers clarifications and practical instructions\u2014aimed mainly at designers and sector professionals\u2014to ensure correct and uniform application of the updated provisions.<\/p>\n\n\n\n<p>In particular, <strong>Use Class IV<\/strong> includes industries with activities that are especially hazardous for the environment, including those subject to Legislative Decree 105\/2015, confirming that such facilities fall among the strategic constructions classified as Class IV.<\/p>\n\n\n\n<p>It specifies that other use classes may be adopted only for parts of a facility that do not affect the initiation, development, or mitigation of a major accident, or are not involved in primary incident scenarios, seismic or otherwise.<\/p>\n\n\n\n<p>It also emphasizes that, as the use class and nominal life increase, the <strong>reference period<\/strong> for seismic design grows, and the <strong>design peak ground acceleration (PGA)<\/strong> increases accordingly.<\/p>\n\n\n\n<p><strong>Earthquake-related NaTech risk for establishments subject to Legislative Decree 105\/2015<\/strong><\/p>\n\n\n\n<p>What is NaTech risk and what are the Operator\u2019s responsibilities?<strong><br><\/strong>The term <strong>NaTech<\/strong> (Natural Hazards Triggering Technological Disasters) refers to technological accidents\u2014<strong>fires, explosions, toxic releases<\/strong>\u2014that can occur in industrial plants or distribution networks when natural disasters strike. For <strong>Major-Accident Hazard (MAH)<\/strong> establishments, assessing these effects requires a <strong>systemic, multidisciplinary<\/strong> approach that considers both <strong>process equipment<\/strong> and <strong>structural<\/strong> aspects.<\/p>\n\n\n\n<p><strong>Legislative Decree 105\/2015<\/strong> incorporates this concept: it recognises that natural events (e.g., earthquakes) can <strong>trigger major accidents<\/strong> and requires the <strong>NaTech analysis<\/strong> to be integrated into the prevention process through appropriate <strong>technical, managerial\/organisational and information<\/strong> measures.<\/p>\n\n\n\n<p>The <strong>Operator<\/strong> has the formal obligation to <strong>assess earthquake-related NaTech risk<\/strong>, as an external event that can <strong>trigger, exacerbate, or hinder the containment<\/strong> of a major accident.<\/p>\n\n\n\n<p>Below is a concise outline of the <strong>key logical steps<\/strong> for setting up the <strong>assessment and management<\/strong> of earthquake-related NaTech risk:<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/lh7-rt.googleusercontent.com\/docsz\/AD_4nXdwRHUWhLZ7AtA3M3y_uJBD0duJ001TlaTkAkyyXv3z-VS4Apcw37LSsxkODjVOKIkOMixdO3TFbZQYAuiinfgINm8va0UmsGVpcy4Z9GiWIqIdcdRYcIzvVc43cHwXdhdvGIhCDw?key=0GGjjFYhD_uGPVg1iOhzdA\" alt=\"Immagine che contiene schermata, testo, diagramma, Carattere\n\nDescrizione generata automaticamente\"\/><\/figure>\n\n\n\n<p>After the safety checks, the operator and the engineer must define a time-phased intervention plan that reflects the identified priorities: the higher the level of inadequacy or the intrinsic hazard of the element, the shorter the timeframe for seismic retrofitting or upgrading must be. If the analysis highlights accident scenarios of particular severity, action should be taken as soon as possible, also adopting compensatory measures (technical, managerial, restrictions on use) to contain the risk.<\/p>\n\n\n\n<p>For existing facilities, NTC 2018, Ch. 8 applies: the safety level is measured with the ratio \u03b6E.<br>\u2022 <strong>Seismic retrofitting<\/strong>: target \u03b6E \u2265 0.80.<br>\u2022 <strong>Seismic improvement<\/strong>: permitted only when 0.80 cannot be achieved for technical\/economic reasons; it still requires \u03b6E \u2265 0.60 and the adoption of technical and managerial mitigation systems.<\/p>\n\n\n\n<p><strong>Major-Accident Hazard establishments \u2013 safety management systems \u2013 guidelines for the application of UNI 10617<\/strong><\/p>\n\n\n\n<p>UNI 10617 defines the Safety Management System for establishments classified as Major-Accident Hazard (MAH). The standard is designed to prevent fires, explosions and toxic releases associated with hazardous substances, and provides a methodological framework that guides the company through all phases: from defining the prevention policy to implementing operating procedures, through to periodic review and continuous improvement of the system. It sets out the organizational and technical requirements needed to establish, implement, maintain and enhance the Safety Management System, supplemented with examples of procedures, monitoring tools and verification criteria.<\/p>\n\n\n\n<p>Its application covers both entire plants and individual technical units in which hazardous substances are produced, used, handled or stored. In essence, UNI 10617 is the primary reference for companies subject to the Seveso regime, providing a comprehensive framework to identify, assess and manage risks in a structured and proactive way, minimizing the likelihood and consequences of accidents.<\/p>\n\n\n\n<p>In summary, for the application of UNI 10617 it is necessary to take into account:<\/p>\n\n\n\n<p><strong>\u2022 Organizational context<\/strong><br>To build or improve the MAH Safety Management System (SGS-PIR), analyze all factors\u2014positive and negative\u2014that may affect the establishment\u2019s safety objectives. Consider both internal and external elements: strategic issues, operational criticalities, and changes that could alter the operator\u2019s ability to achieve the expected results. External factors include, for example, site environmental characteristics and natural hazards (earthquakes, floods, lightning, wildfires, local climatic conditions).<\/p>\n\n\n\n<p><strong>\u2022 Interactions with the context<\/strong><br>The establishment operates within a broader system that includes environmental, social, technological, ethical, political, legal, and economic-financial dimensions. On the environmental side, assess\u2014among many other aspects\u2014potentially triggering natural phenomena (earthquakes, intense meteorological events, floods, landslides, wildfires) \u2014 in line with UNI\/TS 11816-1 on managing earthquake-related NaTech risk \u2014 to understand how they may amplify hazards associated with the hazardous substances present.<\/p>\n\n\n\n<p>In conclusion, for companies at major-accident risk, such as those subject to the Seveso regime, seismic-risk management is a structured journey that considers multiple regulations and factors; it is not merely a compliance task, but a strategic investment that combines safety, environmental protection, and business continuity. With over 1,000 seismic retrofits and deep expertise in Seveso and earthquake-related NaTech risk, Seriana positions itself as an ideal partner to guide each establishment through its seismic upgrading or improvement program.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>At sites governed by the Seveso Directive\u2014classified in Italy as Rischio di Incidente Rilevante (RIR, i.e. Major-Accident Hazard establishments)\u2014seismic strengthening [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":21767,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[39,8],"tags":[],"interventi":[5,40],"class_list":["post-21762","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-anti-seismic-improvement","category-miglioramento-antisismico","interventi-industriale","interventi-industriale-en"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.serianaedilizia.it\/en\/wp-json\/wp\/v2\/posts\/21762","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.serianaedilizia.it\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.serianaedilizia.it\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.serianaedilizia.it\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.serianaedilizia.it\/en\/wp-json\/wp\/v2\/comments?post=21762"}],"version-history":[{"count":2,"href":"https:\/\/www.serianaedilizia.it\/en\/wp-json\/wp\/v2\/posts\/21762\/revisions"}],"predecessor-version":[{"id":22281,"href":"https:\/\/www.serianaedilizia.it\/en\/wp-json\/wp\/v2\/posts\/21762\/revisions\/22281"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.serianaedilizia.it\/en\/wp-json\/wp\/v2\/media\/21767"}],"wp:attachment":[{"href":"https:\/\/www.serianaedilizia.it\/en\/wp-json\/wp\/v2\/media?parent=21762"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.serianaedilizia.it\/en\/wp-json\/wp\/v2\/categories?post=21762"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.serianaedilizia.it\/en\/wp-json\/wp\/v2\/tags?post=21762"},{"taxonomy":"interventi","embeddable":true,"href":"https:\/\/www.serianaedilizia.it\/en\/wp-json\/wp\/v2\/interventi?post=21762"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}