{"id":8713,"date":"2024-05-22T08:49:00","date_gmt":"2024-05-22T06:49:00","guid":{"rendered":"https:\/\/www.idro-elettrica.it\/esperto-risponde\/monitoring-of-fire-protection-water-reserves-uni-en-12845-compliance-check\/"},"modified":"2026-07-01T09:47:22","modified_gmt":"2026-07-01T07:47:22","slug":"monitoring-of-fire-protection-water-reserves-uni-en-12845-compliance-check","status":"publish","type":"esperto-risponde","link":"https:\/\/www.idro-elettrica.it\/en\/esperto-risponde\/monitoring-of-fire-protection-water-reserves-uni-en-12845-compliance-check\/","title":{"rendered":"Monitoring of Fire Protection Water Reserves: UNI EN 12845 Compliance Check"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\"><em>Monitoring the level of the fire protection water reserve<\/em>: Yes, it is required to provide a method for checking\/indicating the level and managing the corresponding alarm, as specified in UNI EN 12845. In this response, we outline the regulatory requirements mentioned and the most commonly used practical solutions. <\/p>\n\n<div class=\"wp-block-rank-math-toc-block\" id=\"rank-math-toc\"><h2>Table of Contents<\/h2><nav><ul><li class=\"\"><a href=\"#cosa-richiede-la-uni-en-12845-al-punto-9-3-2-1\">What does UNI EN 12845 require in section 9.3.2.1?<\/a><\/li><li class=\"\"><a href=\"#cosa-aggiungono-app-h-e-app-i-prospetto-i-1\">What do APP. H and APP. I (Table I.1) add? <\/a><\/li><li class=\"\"><a href=\"#soluzione-1-indicatore-di-livello-leggibile-dallesterno-livellostato\">Solution 1: Level indicator visible from the outside + level switch<\/a><\/li><li class=\"\"><a href=\"#soluzione-2-indicatore-visivo-dotato-di-contatti-elettrici\">Solution 2: Visual indicator equipped with electrical contacts<\/a><\/li><li class=\"\"><a href=\"#soluzione-3-sensore-di-livello-immerso-con-segnale-4-20-m-a\">Solution 3: Submerged level sensor with a 4\u201320 mA signal<\/a><\/li><li class=\"\"><a href=\"#collegamento-alla-centralina-della-pompa-e-trasmissione-dellallarme\">Connection to the pump control unit and alarm transmission<\/a><\/li><li class=\"\"><a href=\"#quale-soluzione-scegliere-in-base-a-cosa-serve-davvero\">Which Solution to Choose (Based on What You Actually Need)<\/a><\/li><li class=\"\"><a href=\"#conclusione\">Conclusion<\/a><\/li><\/ul><\/nav><\/div>\n\n<h2 id=\"cosa-richiede-la-uni-en-12845-al-punto-9-3-2-1\" class=\"wp-block-heading\">What does UNI EN 12845 require in section 9.3.2.1?<\/h2>\n\n<p class=\"wp-block-paragraph\">UNI EN 12845 addresses this issue in section <strong>9.3.2.1<\/strong>, stating that, <strong>with the exception of open basins<\/strong>, tanks must be equipped with <strong>a water level indicator that is readable from the outside<\/strong>.<\/p>\n\n<p class=\"wp-block-paragraph\">In practice, the requirement isn&#8217;t just to &#8220;know&#8221; that there is water: we need a system that makes <strong>it possible to<\/strong> clearly verify the water level in the cistern or tank from the outside.<\/p>\n\n<h2 id=\"cosa-aggiungono-app-h-e-app-i-prospetto-i-1\" class=\"wp-block-heading\">What do APP. H and APP. I (Table I.1) add? <\/h2>\n\n<p class=\"wp-block-paragraph\">In addition to the \u201cvisual\u201d requirement in 9.3.2.1, in the  <strong>APP. H <\/strong>  (Fluid Levels) All critical fluid levels, including <strong>water storage tanks<\/strong>, must be monitored <strong>so<\/strong> that the water level does not fall <strong>more than 10% below the nominal fill level<\/strong>.<\/p>\n\n<p class=\"wp-block-paragraph\">Finally, in the  <strong>APP. I <\/strong>, in <strong>Table I.1<\/strong> (list of <strong>alarms to be transmitted<\/strong>), the <strong>liquid level<\/strong> (including the water reserve level) is listed among the <strong>Type B alarms (technical alarms)<\/strong> that must <strong>be monitored and transmitted to a manned area<\/strong>.<\/p>\n\n<h2 id=\"soluzione-1-indicatore-di-livello-leggibile-dallesterno-livellostato\" class=\"wp-block-heading\">Solution 1: Level indicator visible from the outside + level switch<\/h2>\n\n<p class=\"wp-block-paragraph\">To comply with the requirement in <strong>9.3.2.1<\/strong>, a <strong>simple level indicator<\/strong> (such as the one mentioned in the example) may be used.<\/p>\n\n<p class=\"wp-block-paragraph\">This indicator must <strong>be accompanied<\/strong> by <strong>a level switch<\/strong> (such as a <strong>float switch<\/strong>) capable of triggering an <strong>alarm contact<\/strong> when the level specified by the  <strong>APP. H <\/strong>  (that is, before the decline exceeded 10% from the nominal level).<\/p>\n\n<p class=\"wp-block-paragraph\">With this combination, you get:<\/p>\n\n<ul class=\"wp-block-list\">\n<li><strong>external level reading<\/strong> (indicator);<\/li>\n\n\n\n<li><strong>generation of the alarm contact<\/strong> (level switch\/float switch);<\/li>\n\n\n\n<li>willingness to <strong>monitor and trigger the alarm<\/strong> as required.<\/li>\n<\/ul>\n\n<h2 id=\"soluzione-2-indicatore-visivo-dotato-di-contatti-elettrici\" class=\"wp-block-heading\">Solution 2: Visual indicator equipped with electrical contacts<\/h2>\n\n<p class=\"wp-block-paragraph\">Alternatively, you can install a <strong>visual indicator<\/strong> that <strong>is<\/strong> already <strong>equipped with electrical contacts<\/strong>.<\/p>\n\n<p class=\"wp-block-paragraph\">In this case, the indicator\u2019s contacts can be used directly as <strong>alarm contacts<\/strong> and <strong>routed to a manned station<\/strong>, in accordance with the provisions regarding technical alarms (APP. I, Table I.1) and the indication threshold specified in APP. H. <\/p>\n\n<p class=\"wp-block-paragraph\">The practical advantage of this option, compared to the \u201cindicator + float\u201d solution, is that the visual indicator and the contacts are integrated into the same device, while still achieving the goal of <strong>displaying the level<\/strong> and <strong>triggering the alarm<\/strong>.<\/p>\n\n<h2 id=\"soluzione-3-sensore-di-livello-immerso-con-segnale-4-20-m-a\" class=\"wp-block-heading\">Solution 3: Submerged level sensor with a 4\u201320 mA signal<\/h2>\n\n<p class=\"wp-block-paragraph\">According to the description, the simplest method for <strong>monitoring the level of the fire protection water reservoir<\/strong> and triggering the required alarm is to use a <strong>level sensor submerged<\/strong> in the reservoir that provides a <strong>4\u201320 mA<\/strong> signal <strong>proportional to the free-surface level<\/strong>.<\/p>\n\n<p class=\"wp-block-paragraph\">This setting provides a \u201ccontinuous\u201d (proportional) signal, which is useful both for level indication and for managing the required alarm threshold (APP. H), without compromising the objective: ensuring legible display and alarm transmission as specified in APP. I. <\/p>\n\n<h2 id=\"collegamento-alla-centralina-della-pompa-e-trasmissione-dellallarme\" class=\"wp-block-heading\">Connection to the pump control unit and alarm transmission<\/h2>\n\n<p class=\"wp-block-paragraph\">The sensor can be connected to <strong>the electronic control unit of one of the main fire pumps<\/strong>, so as to:<\/p>\n\n<ul class=\"wp-block-list\">\n<li><strong>always display<\/strong> the tank level <strong>on the screen<\/strong> (in accordance with the requirement in <strong>9.3.2.1<\/strong> regarding level indication);<\/li>\n\n\n\n<li>be able to <strong>manage and transmit the<\/strong> <strong>low-level tank<\/strong> <strong>alarm<\/strong>, as required by the other sections referenced (APP. H for the indication threshold and APP. I\/Table I.1 for the alarm to be sent to <strong>the manned area<\/strong>).  <\/li>\n<\/ul>\n\n<p class=\"wp-block-paragraph\">In summary: level indication and alarm generation\/transmission are two sides of the same operational requirement.<\/p>\n\n<h2 id=\"quale-soluzione-scegliere-in-base-a-cosa-serve-davvero\" class=\"wp-block-heading\">Which Solution to Choose (Based on What You Actually Need)<\/h2>\n\n<p class=\"wp-block-paragraph\">The three options described lead to the same goal: <strong>meeting the requirements cited<\/strong> (9.3.2.1, APP. H, APP. I) without unnecessarily complicating the system.<\/p>\n\n<p class=\"wp-block-paragraph\">In terms of functional logic:<\/p>\n\n<ul class=\"wp-block-list\">\n<li>If an immediate visual check is the main requirement,<strong>the externally readable indicator<\/strong> is the basis;<\/li>\n\n\n\n<li>If an alarm is also needed, <strong>contacts<\/strong> are required (from a level switch\/float switch or built into the indicator);<\/li>\n\n\n\n<li>If you want direct and proportional monitoring, the <strong>submersible 4-20 mA sensor<\/strong> provides a dedicated signal that can be processed by the control unit, while keeping both the display and the alarm active.<\/li>\n<\/ul>\n\n<h2 id=\"conclusione\" class=\"wp-block-heading\">Conclusion<\/h2>\n\n<p class=\"wp-block-paragraph\">For a tank used as a fire protection water reserve, a system must be provided that allows<strong>the level to be read from the outside<\/strong> (UNI EN 12845, 9.3.2.1) and that enables<strong>a low-level alarm<\/strong> to <strong>be generated and transmitted<\/strong> (APP. H and APP. I\/Table I.1) to a <strong>manned area<\/strong>. Solutions may be simple (gauge + float), integrated (gauge with contacts), or signal-based (4\u201320 mA sensor). <\/p>\n","protected":false},"excerpt":{"rendered":"<p>Monitoring the Level of Fire Protection Water Reserves: Is It Really Necessary to Install a Tank Level Monitor? Let\u2019s take a look at the requirements of UNI EN 12845 (9.3.2.1, Annex H, and Annex I) and explore practical solutions that allow you to monitor the level and transmit a low-level alarm to a manned area. <\/p>\n","protected":false},"featured_media":8715,"parent":0,"template":"","meta":{"_acf_changed":false,"_angie_page":false,"footnotes":"","_members_access_role":[],"_members_access_error":""},"tags":[1159,669,707,1155,1158,1157,1160,1156,549],"class_list":["post-8713","esperto-risponde","type-esperto-risponde","status-publish","has-post-thumbnail","hentry","tag-4-20-ma","tag-fire-protection-water-supply-2","tag-fire-suppression-tank","tag-level-monitoring","tag-level-switch","tag-low-water-level-in-the-tub","tag-secured-area","tag-technical-alerts","tag-uni-en-12845"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/esperto-risponde\/8713","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/esperto-risponde"}],"about":[{"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/types\/esperto-risponde"}],"version-history":[{"count":0,"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/esperto-risponde\/8713\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/media\/8715"}],"wp:attachment":[{"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/media?parent=8713"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.idro-elettrica.it\/en\/wp-json\/wp\/v2\/tags?post=8713"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}