{"id":100198,"date":"2026-02-15T20:26:18","date_gmt":"2026-02-15T20:26:18","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100198"},"modified":"2026-07-13T05:31:27","modified_gmt":"2026-07-13T05:31:27","slug":"pressure-vessel-en13445","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/it\/calculators\/pressure-vessel-en13445\/","title":{"rendered":"Controlled Pressure-Vessel Thickness Record Comparator"},"content":{"rendered":"\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Controlled Pressure-Vessel Thickness Record Comparator\",\"description\":\"Compare a documented code-calculated thickness plus explicitly authorized additive allowances with a documented minimum credited thickness, without reproducing or claiming ASME or EN design rules.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/pressure-vessel-en13445\/\",\"applicationCategory\":\"EngineeringApplication\",\"operatingSystem\":\"Any\",\"offers\":{\"@type\":\"Offer\",\"price\":\"0\"},\"creator\":{\"@type\":\"Organization\",\"name\":\"Vibromera\",\"url\":\"https:\/\/vibromera.eu\/\"},\"dateModified\":\"2026-07-13\",\"inLanguage\":\"en\",\"isAccessibleForFree\":true}<\/script>\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[{\"@type\":\"Question\",\"name\":\"Does this worksheet calculate pressure-vessel wall thickness to ASME or EN 13445?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"No. It deliberately does not reproduce licensed code formulas. It only checks arithmetic between thickness values already established and documented by an approved code calculation.\"}},{\"@type\":\"Question\",\"name\":\"What is documented calculation thickness?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"It is the thickness value taken from the identified approved calculation at the stated component location and basis. Its exact definition is controlled by that calculation and governing code.\"}},{\"@type\":\"Question\",\"name\":\"What belongs in additive allowance?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Only thickness that the controlled calculation explicitly instructs you to add arithmetically to the documented calculation thickness. Do not invent a generic corrosion or wear allowance.\"}},{\"@type\":\"Question\",\"name\":\"What is minimum credited thickness?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"It is the minimum thickness the approved calculation permits you to credit at the same location and basis after every applicable non-additive deduction or tolerance has been handled by the controlled process.\"}},{\"@type\":\"Question\",\"name\":\"Does an above or equal comparison prove code compliance?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"No. The relation is only arithmetic. Code applicability, inputs, formulas, load cases, materials, fabrication, examination, testing, jurisdiction and approval remain outside this worksheet.\"}}]}<\/script>\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"BreadcrumbList\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/vibromera.eu\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Calculators\",\"item\":\"https:\/\/vibromera.eu\/calculators\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Pressure-vessel thickness record 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1fr}.vc-result-grid{grid-template-columns:1fr 1fr}}@media(max-width:560px){.vc-grid,.vc-result-grid{grid-template-columns:1fr}.vc-form,.vc-results{padding:18px}.vc-results-head{align-items:flex-start;flex-direction:column}}@media print{.vc-section-body,.vc-results{display:block!important}.vc-copy,.vc-chevron,.vc-actions{display:none}}\n<\/style>\n<div class=\"vc-calculator\">\n<header class=\"vc-header\"><p class=\"vc-eyebrow\">Evidence-controlled arithmetic \u00b7 not code sizing<\/p><h1 class=\"vc-title\">Controlled Pressure-Vessel Thickness Record Comparator<\/h1><p class=\"vc-subtitle\">Compare a thickness already established by an approved licensed-code calculation, plus only its explicitly authorized additive allowances, with a minimum credited thickness on the same documented basis.<\/p><div class=\"vc-badges\"><span class=\"vc-badge\">No ASME\/EN formulas reproduced<\/span><span class=\"vc-badge\">Exact mm \u2194 in route<\/span><span class=\"vc-badge\">No compliance verdict<\/span><\/div><\/header>\n<div class=\"vc-card\"><form class=\"vc-form\" id=\"vc-form\" novalidate><div class=\"vc-grid\">\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-units\">Thickness unit<\/label><select class=\"vc-select\" id=\"vc-units\"><option value=\"mm\">Millimetres (mm)<\/option><option value=\"in\">Inches (in)<\/option><\/select><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-code\">Governing record basis<\/label><select class=\"vc-select\" id=\"vc-code\"><option value=\"\">Select the documented basis<\/option><option value=\"asme2025\">ASME BPVC VIII.1-2025<\/option><option value=\"en2026\">EN 13445-3:2026 \/ stated national adoption<\/option><option value=\"other\">Other exact controlled code\/edition<\/option><\/select><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-component\">Component \/ calculation location<\/label><input class=\"vc-input\" id=\"vc-component\" autocomplete=\"off\" placeholder=\"e.g. shell course C-01 at longitudinal joint\"><\/div>\n<div class=\"vc-field vc-wide\"><label class=\"vc-label\" for=\"vc-basis\">Approved calculation \/ document reference<\/label><input class=\"vc-input\" id=\"vc-basis\" autocomplete=\"off\" placeholder=\"Document number, revision, sheet\/clause and approving authority\"><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-required\">Documented calculation thickness t<sub>calc<\/sub> <span class=\"vc-hint vc-unit-hint\">(mm)<\/span><\/label><input class=\"vc-input\" id=\"vc-required\" inputmode=\"decimal\" autocomplete=\"off\"><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-additive\">Authorized additive allowance c<sub>add<\/sub> <span class=\"vc-hint vc-unit-hint\">(mm)<\/span><\/label><input class=\"vc-input\" id=\"vc-additive\" inputmode=\"decimal\" autocomplete=\"off\"><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-available\">Minimum credited thickness t<sub>credit<\/sub> <span class=\"vc-hint vc-unit-hint\">(mm)<\/span><\/label><input class=\"vc-input\" id=\"vc-available\" inputmode=\"decimal\" autocomplete=\"off\"><\/div>\n<label class=\"vc-check vc-wide\" for=\"vc-confirm\"><input id=\"vc-confirm\" type=\"checkbox\"><span>I confirm that t<sub>calc<\/sub>, c<sub>add<\/sub> and t<sub>credit<\/sub> come from the identified approved calculation\/process for the same component location, edition, geometry basis and units; c<sub>add<\/sub> contains only explicitly additive items; t<sub>credit<\/sub> already handles every applicable non-additive tolerance\/deduction as required by that process; and I will not treat this arithmetic relation as code compliance.<\/span><\/label>\n<div class=\"vc-actions vc-wide\"><button class=\"vc-calc-btn\" type=\"submit\">Compare documented thickness records<\/button><\/div>\n<\/div><\/form><div class=\"vc-error\" id=\"vc-error\" role=\"alert\"><\/div>\n<div class=\"vc-results\" id=\"vc-results\" aria-live=\"polite\"><div class=\"vc-results-head\"><div><h2 class=\"vc-results-title\">Arithmetic comparison<\/h2><div class=\"vc-results-basis\" id=\"vc-results-basis\">\u2014<\/div><\/div><button type=\"button\" class=\"vc-copy\" id=\"vc-copy\">Copy record<\/button><\/div><div class=\"vc-result-grid\">\n<div class=\"vc-result vc-primary\"><div class=\"vc-result-label\">Documented arithmetic total tcalc + cadd<\/div><div class=\"vc-result-value\" id=\"vc-total\">\u2014<\/div><\/div>\n<div class=\"vc-result\"><div class=\"vc-result-label\">Minimum credited thickness<\/div><div class=\"vc-result-value\" id=\"vc-credit\">\u2014<\/div><\/div>\n<div class=\"vc-result\"><div class=\"vc-result-label\">Arithmetic margin tcredit \u2212 total<\/div><div class=\"vc-result-value\" id=\"vc-margin\">\u2014<\/div><\/div>\n<div class=\"vc-result\"><div class=\"vc-result-label\">Arithmetic ratio tcredit \/ total<\/div><div class=\"vc-result-value\" id=\"vc-ratio\">\u2014<\/div><\/div>\n<\/div><div class=\"vc-relation\" id=\"vc-relation\">\u2014<\/div><div class=\"vc-warning\"><strong>Not code acceptance:<\/strong> \u201cabove\u201d, \u201cequal\u201d or \u201cbelow\u201d describes only the entered numbers. It does not validate their definitions, the original code calculation, nominal plate selection, tolerances, load cases, fabrication, examination, test or legal conformity.<\/div><\/div><\/div>\n\n<section class=\"vc-section vc-open\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"true\"><span class=\"vc-section-title\">The only arithmetic performed<\/span><span class=\"vc-chevron\">\u2304<\/span><\/button><div class=\"vc-section-body\"><div class=\"vc-section-inner\">\n<h3>Same-basis record comparison<\/h3><div class=\"vc-formula\">t<sub>documented,total<\/sub> = t<sub>calc<\/sub> + c<sub>add<\/sub><br>margin = t<sub>credit<\/sub> \u2212 t<sub>documented,total<\/sub><br>ratio = t<sub>credit<\/sub> \/ t<sub>documented,total<\/sub><\/div>\n<p>All three thickness inputs must refer to the same physical component location and compatible thickness definition. The worksheet converts inches to millimetres internally with exactly 1 in = 25.4 mm, performs addition\/subtraction\/division, and returns the selected display unit.<\/p>\n<p>A positive margin means only that the entered credited value is numerically above the entered arithmetic total; zero means equal; a negative margin means below. No safety factor, allowable stress, joint coefficient, head coefficient, pressure formula or code acceptance rule is applied.<\/p>\n<div class=\"vc-danger\"><strong>Do not substitute nominal plate thickness blindly:<\/strong> t<sub>credit<\/sub> is the minimum thickness the approved process permits you to credit at the comparison location and basis. Nominal thickness may require mill tolerance, forming thinning, corrosion\/erosion treatment or other deductions that this page cannot infer.<\/div>\n<\/div><\/div><\/section>\n<section class=\"vc-section\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-title\">Why the former design calculator was withdrawn<\/span><span class=\"vc-chevron\">\u2304<\/span><\/button><div class=\"vc-section-body\"><div class=\"vc-section-inner\">\n<p>The former page claimed minimum shell and head thicknesses to EN 13445 and ASME Section VIII from pressure, outside diameter, a fixed material value, a generic weld factor and corrosion allowance. That claim was not supportable.<\/p>\n<div class=\"vc-table-wrap\"><table class=\"vc-table\"><thead><tr><th>Former component<\/th><th>Confirmed problem<\/th><\/tr><\/thead><tbody>\n<tr><td>Design temperature<\/td><td>Collected but never used. Hard-coded allowable stresses therefore did not change with temperature.<\/td><\/tr>\n<tr><td>Material presets<\/td><td>Fixed values were shown without a verified edition, product form, temperature row, notes or code-source traceability; ASME SA material labels were also offered under the EN route.<\/td><\/tr>\n<tr><td>Joint \/ weld factors<\/td><td>Generic 1.0, 0.85 and 0.7 choices were applied to both code systems without verified joint category, examination scope or licensed rule.<\/td><\/tr>\n<tr><td>Cylindrical formula<\/td><td>The displayed ASME inner-radius equation differed from the outside-diameter equation executed by JavaScript. The worked example used another radius approximation while the default route was EN.<\/td><\/tr>\n<tr><td>Heads<\/td><td>Hemispherical and ellipsoidal equations were labelled code formulas while runtime comments called them approximations or simplifications. Flat-head coefficients 0.33 and 0.35 were hard-coded as \u201ctypical\u201d without geometry\/attachment scope.<\/td><\/tr>\n<tr><td>Corrosion and plate recommendation<\/td><td>Universal service allowances and \u201cuse 12 mm plate minimum\u201d ignored the controlled corrosion basis, negative tolerance, forming, other loads and code-specific requirements.<\/td><\/tr>\n<\/tbody><\/table><\/div>\n<p>Changing one coefficient would conceal rather than fix these root causes. The unsupported formula engine, presets, automatic results and code-compliance language were removed.<\/p>\n<\/div><\/div><\/section>\n<section class=\"vc-section\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-title\">What the approved code calculation must establish<\/span><span class=\"vc-chevron\">\u2304<\/span><\/button><div class=\"vc-section-body\"><div class=\"vc-section-inner\">\n<p>This list is a scope reminder, not a substitute for either code. The responsible approved calculation must determine what applies, including:<\/p><ul><li>jurisdiction, exact governing code\/edition\/addenda and component scope;<\/li><li>design, operating, test and external pressures; temperatures and coincident load cases;<\/li><li>component geometry, diameter\/thickness convention, heads, openings, nozzles, supports and discontinuities;<\/li><li>material specification, product form, temperature-dependent allowable basis and degradation mechanisms;<\/li><li>joint category, weld details, examination extent, applicable coefficient and fabrication route;<\/li><li>corrosion\/erosion allowance, design life, negative material tolerance, forming thinning and credited minimum thickness;<\/li><li>external-pressure stability, local loads, wind\/seismic\/dead weight, thermal effects, fatigue, creep, fracture and cyclic service as applicable;<\/li><li>reinforcement, inspection, nondestructive examination, pressure testing, overpressure protection, documentation and authorized approval.<\/li><\/ul>\n<div class=\"vc-warning\"><strong>Definitions control:<\/strong> whether an allowance is added to a calculated thickness, deducted from an available thickness, embedded elsewhere or handled by another rule cannot be decided by this page. Follow the licensed code and the approved project calculation exactly.<\/div>\n<\/div><\/div><\/section>\n<section class=\"vc-section\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-title\">Current source status and access boundary<\/span><span class=\"vc-chevron\">\u2304<\/span><\/button><div class=\"vc-section-body\"><div class=\"vc-section-inner\">\n<h3>ASME BPVC Section VIII, Division 1<\/h3><p>The official <a href=\"https:\/\/www.asme.org\/codes-standards\/find-codes-standards\/bpvc-viii-1-bpvc-section-viii-rules-construction-pressure-vessels-division-1\" target=\"_blank\" rel=\"noopener\">ASME BPVC.VIII.1-2025 product page<\/a> describes requirements for design, fabrication, inspection, testing and certification of vessels within its scope, with material\/fabrication requirements and mandatory and nonmandatory appendices. This public scope confirms why a few generic equations cannot establish conformity; detailed rules require authorized access.<\/p>\n<h3>EN 13445-3<\/h3><p>The official national-standards-body page for <a href=\"https:\/\/app.nbn.be\/data\/r\/platform\/frontend\/detail?p40_id=3550995&amp;p_lang=en\" target=\"_blank\" rel=\"noopener\">NBN EN 13445-3:2026<\/a> identifies it as active from 2 July 2026, replacing NBN EN 13445-3:2021+A1:2026. Its scope is design of unfired pressure vessels covered by EN 13445-1:2026 and constructed of steels under EN 13445-2:2026. Detailed rules remain licensed, and the applicable national adoption\/jurisdiction must be confirmed.<\/p>\n<h3>Length conversion<\/h3><p><a href=\"https:\/\/www.nist.gov\/pml\/special-publication-811\/nist-guide-si-appendix-b-conversion-factors\/nist-guide-si-appendix-b8\" target=\"_blank\" rel=\"noopener\">NIST SP 811 Appendix B.8<\/a> lists 1 inch = 0.0254 metre and marks exact factors in bold. Therefore 1 in = 25.4 mm and the official unit check 0.5 in = 12.7 mm is exact.<\/p>\n<p>Sources and lifecycle status accessed 13 July 2026. No ASME\/EN clause number, table value or formula is asserted without the licensed text.<\/p>\n<\/div><\/div><\/section>\n<section class=\"vc-section\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-title\">Frequently asked questions<\/span><span class=\"vc-chevron\">\u2304<\/span><\/button><div class=\"vc-section-body\"><div class=\"vc-section-inner\">\n<div class=\"vc-faq\"><button type=\"button\">Does this calculate a shell or head thickness to ASME or EN 13445?<\/button><div>No. The former unsupported formula engine was removed. Enter only values already established by the identified approved licensed-code calculation.<\/div><\/div>\n<div class=\"vc-faq\"><button type=\"button\">What goes in additive allowance?<\/button><div>Only items the controlled calculation explicitly requires to be added arithmetically at the same component location and thickness basis. Zero is valid. Do not insert generic corrosion values.<\/div><\/div>\n<div class=\"vc-faq\"><button type=\"button\">Can I enter nominal plate thickness as tcredit?<\/button><div>Only if the approved process explicitly permits that exact value to be credited after all applicable tolerance,forming and other deductions. This page cannot make that determination.<\/div><\/div>\n<div class=\"vc-faq\"><button type=\"button\">Does a non-negative margin mean the vessel complies?<\/button><div>No. It is only the relation between three entered thickness records. The code calculation and every governing design,fabrication,inspection,test and approval requirement remain external.<\/div><\/div>\n<div class=\"vc-faq\"><button type=\"button\">Why are material and weld-efficiency presets gone?<\/button><div>Their correct values depend on exact code edition,material\/product form,temperature,joint\/examination scope and other licensed rules. Generic presets created false certainty.<\/div><\/div>\n<\/div><\/div><\/section>\n<section class=\"vc-section\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-title\">Related worksheets<\/span><span class=\"vc-chevron\">\u2304<\/span><\/button><div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div class=\"vc-related\"><a href=\"\/calculators\/pressure-vessel-calculator\/\">General thin-cylinder membrane stress<\/a><a href=\"\/calculators\/pressure-unit-converter\/\">Defined pressure units<\/a><a href=\"\/calculators\/pipe-wall-thickness-pressure\/\">Pipe wall worksheet<\/a><\/div><\/div><\/div><\/section>\n<footer class=\"vc-footer\">Controlled-record arithmetic only; preserve the approved calculation, revision and definition of every entered thickness. \u00b7 <a href=\"\/calculators\/engineering-calculators\/\">All calculators<\/a><\/footer>\n<\/div>\n<script>\n(function(){\n\"use strict\";\nvar INCH_MM=25.4,CODES=['asme2025','en2026','other'];\nfunction byId(id){return document.getElementById(id)}\nfunction parseNumber(text){var s=String(text).trim();if(!s||s.indexOf('.')>=0&&s.indexOf(',')>=0||!\/^[-+]?(?:\\d+(?:[.,]\\d*)?|[.,]\\d+)(?:[eE][-+]?\\d+)?$\/.test(s))return null;var n=Number(s.replace(',','.'));return Number.isFinite(n)?n:null}\nfunction toMillimetres(value,unit){if(!Number.isFinite(value))throw new Error('Thickness must be finite.');if(unit==='mm')return value;if(unit==='in')return value*INCH_MM;throw new Error('Choose a supported thickness unit.')}\nfunction thicknessRecordCompare(x){if(!x||!Number.isFinite(x.calculationMm)||!Number.isFinite(x.additiveMm)||!Number.isFinite(x.creditedMm))throw new Error('Every thickness must be finite.');if(x.calculationMm<=0)throw new Error('Documented calculation thickness must be greater than zero.');if(x.additiveMm<0)throw new Error('Authorized additive allowance must be zero or greater.');if(x.creditedMm<=0)throw new Error('Minimum credited thickness must be greater than zero.');var total=x.calculationMm+x.additiveMm;if(!Number.isFinite(total)||total<=0)throw new Error('The arithmetic total is outside the finite numeric range.');var margin=x.creditedMm-total,ratio=x.creditedMm\/total;if(!Number.isFinite(margin)||!Number.isFinite(ratio))throw new Error('A comparison result is outside the finite numeric range.');var tolerance=8*Number.EPSILON*Math.max(1,Math.abs(total),Math.abs(x.creditedMm));var relation=margin>tolerance?'above':margin<-tolerance?'below':'equal';return{totalMm:total,creditedMm:x.creditedMm,marginMm:margin,ratio:ratio,relation:relation,toleranceMm:tolerance}}\nwindow.vbmThicknessRecordCompare=thicknessRecordCompare;window.vbmThicknessToMm=toMillimetres;window.vbmThicknessParse=parseNumber;window.vbmThicknessConstants={INCH_MM:INCH_MM};\nfunction fmt(n){if(n===0||Object.is(n,-0))return'0';var a=Math.abs(n),s;if(a>=1e9||a<1e-6)s=n.toExponential(9);else s=n.toPrecision(10);return s.replace(\/(\\.\\d*?[1-9])0+(e|$)\/,'$1$2').replace(\/\\.0+(e|$)\/,'$1').replace('e+','e')}\nfunction codeLabel(key){return key==='asme2025'?'ASME BPVC VIII.1-2025':key==='en2026'?'EN 13445-3:2026 \/ stated national adoption':'other exact controlled code\/edition'}\nfunction fail(message){byId('vc-error').textContent=message;byId('vc-error').classList.add('vc-show');byId('vc-results').classList.remove('vc-visible')}\nfunction hideOutput(){byId('vc-error').classList.remove('vc-show');byId('vc-results').classList.remove('vc-visible')}\nfunction clearNumbers(){['vc-required','vc-additive','vc-available'].forEach(function(id){byId(id).value='' });byId('vc-confirm').checked=false;hideOutput()}\nfunction calculate(){var required=parseNumber(byId('vc-required').value),additive=parseNumber(byId('vc-additive').value),available=parseNumber(byId('vc-available').value),unit=byId('vc-units').value,code=byId('vc-code').value,component=byId('vc-component').value.trim(),basis=byId('vc-basis').value.trim();if(CODES.indexOf(code)<0)return fail('Select the exact governing record basis. For Other, identify the exact code and edition in the approved document reference.');if(!component)return fail('Enter the component and calculation location.');if(!basis)return fail('Enter the approved calculation\/document number,revision and location.');if(required===null||additive===null||available===null)return fail('Enter three complete finite thickness values. A comma may replace the decimal point; do not use thousands separators or unit suffixes.');if(!byId('vc-confirm').checked)return fail('Confirm the same-basis record and non-compliance conditions before comparing.');var result;try{result=thicknessRecordCompare({calculationMm:toMillimetres(required,unit),additiveMm:toMillimetres(additive,unit),creditedMm:toMillimetres(available,unit)})}catch(error){return fail(error.message)}var factor=unit==='mm'?1:1\/INCH_MM,symbol=unit;byId('vc-error').classList.remove('vc-show');byId('vc-total').textContent=fmt(result.totalMm*factor)+' '+symbol;byId('vc-credit').textContent=fmt(result.creditedMm*factor)+' '+symbol;var displayedMargin=result.marginMm*factor;byId('vc-margin').textContent=(displayedMargin>0?'+':'')+fmt(displayedMargin)+' '+symbol;byId('vc-ratio').textContent=fmt(result.ratio);var relation=byId('vc-relation');relation.classList.toggle('vc-below',result.relation==='below');relation.textContent=result.relation==='above'?'Arithmetic relation: entered minimum credited thickness is ABOVE the entered documented total by '+fmt(Math.abs(displayedMargin))+' '+symbol+'.':result.relation==='below'?'Arithmetic relation: entered minimum credited thickness is BELOW the entered documented total by '+fmt(Math.abs(displayedMargin))+' '+symbol+'.':'Arithmetic relation: entered minimum credited thickness is EQUAL to the entered documented total within floating-point comparison tolerance.';byId('vc-results-basis').textContent=codeLabel(code)+' \u00b7 '+component+' \u00b7 '+basis;byId('vc-results').dataset.relation=result.relation;byId('vc-results').classList.add('vc-visible')}\nbyId('vc-form').addEventListener('submit',function(e){e.preventDefault();calculate()});byId('vc-form').addEventListener('input',hideOutput);byId('vc-form').addEventListener('change',hideOutput);byId('vc-units').addEventListener('change',function(){var symbol=this.value==='mm'?'mm':'in';document.querySelectorAll('.vc-unit-hint').forEach(function(node){node.textContent='('+symbol+')'});clearNumbers()});document.querySelectorAll('.vc-section-toggle').forEach(function(button){button.addEventListener('click',function(){var section=this.closest('.vc-section');section.classList.toggle('vc-open');this.setAttribute('aria-expanded',section.classList.contains('vc-open')?'true':'false')})});document.querySelectorAll('.vc-faq button').forEach(function(button){button.addEventListener('click',function(){this.parentNode.classList.toggle('vc-open')})});byId('vc-copy').addEventListener('click',function(){if(!byId('vc-results').classList.contains('vc-visible')||!navigator.clipboard)return;var lines=[byId('vc-results-basis').textContent,'Documented arithmetic total: '+byId('vc-total').textContent,'Minimum credited thickness: '+byId('vc-credit').textContent,'Arithmetic margin: '+byId('vc-margin').textContent,'Arithmetic ratio: '+byId('vc-ratio').textContent,byId('vc-relation').textContent,'Arithmetic record comparison only;not ASME\/EN code calculation or compliance.'];navigator.clipboard.writeText(lines.join('\\n'))});\n})();\n<\/script>\n","protected":false},"excerpt":{"rendered":"<p>Compare documented code-calculated thickness records and authorized additive allowances without reproducing or claiming ASME or EN design rules.<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100198","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/it\/wp-json\/wp\/v2\/calculator\/100198","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/it\/wp-json\/wp\/v2\/calculator"}],"about":[{"href":"https:\/\/vibromera.eu\/it\/wp-json\/wp\/v2\/types\/calculator"}],"version-history":[{"count":3,"href":"https:\/\/vibromera.eu\/it\/wp-json\/wp\/v2\/calculator\/100198\/revisions"}],"predecessor-version":[{"id":102539,"href":"https:\/\/vibromera.eu\/it\/wp-json\/wp\/v2\/calculator\/100198\/revisions\/102539"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/it\/wp-json\/wp\/v2\/media?parent=100198"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/it\/wp-json\/wp\/v2\/categories?post=100198"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/it\/wp-json\/wp\/v2\/tags?post=100198"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}