{"id":18007,"date":"2017-10-30T08:00:49","date_gmt":"2017-10-30T15:00:49","guid":{"rendered":"http:\/\/www.autodesk.com\/products\/eagle\/blog\/?p=1848"},"modified":"2023-07-18T15:11:55","modified_gmt":"2023-07-18T22:11:55","slug":"ul-certification-for-electronics-design","status":"publish","type":"post","link":"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/ul-certification-for-electronics-design\/","title":{"rendered":"What You Need to Know About UL Certification as an Electronics Designer"},"content":{"rendered":"\n<p><span style=\"font-weight: 400;\">Safety is always a concern in the back of an engineer\u2019s mind. Even with all the simulations in the world, you still wonder how your PCB will perform under a variety of temperatures, environmental conditions, and handlings in its physical form. This can only be verified with thorough testing. If you\u2019re planning to design PCBs for information technology, audio, video, medical, or appliance applications, then you\u2019ll need to be certified with the utmost safety standards. This means dealing with the details of UL certification. In this blog, we\u2019ll be looking at what UL certification, what kind of standards it requires for PCB designs, and how this certification affects your job as an electronics design. <\/span><\/p>\n\n\n<h2 class=\"wp-block-heading\" id=\"what-is-ul\">What is UL?<\/h2>\n\n\n<p><a href=\"http:\/\/www.ul.com\/\"><span style=\"font-weight: 400;\">The Underwriters Laboratory (UL)<\/span><\/a><span style=\"font-weight: 400;\"> was founded in 1894 by William Henry Merrill, an American electrical engineer. UL is an independent, international organization that tests products, certifies manufacturers and documents safety standards for a diverse range of industries and applications.<\/span><\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-large size-full wp-image-1850\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"1024\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/UL_Mark.svg_-1024x1024.png\" alt=\"underwriters laboratory\" class=\"wp-image-59767\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/UL_Mark.svg_-1024x1024.png 1024w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/UL_Mark.svg_-300x300.png 300w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/UL_Mark.svg_-150x150.png 150w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/UL_Mark.svg_-768x768.png 768w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/UL_Mark.svg_-345x345.png 345w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/UL_Mark.svg_.png 1200w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\"><em>Underwriters Laboratory, making products safer since 1894. (<a href=\"http:\/\/www.ul.com\/\">Image source<\/a>)<\/em><\/figcaption><\/figure>\n\n\n\n<p><span style=\"font-weight: 400;\">The UL Mark that Underwriters Laboratory offers is a well-known symbol of product safety in the electronics manufacturing industry. There are more than 17 billion UL marks added to new products every year, and their next mark might be on your board. UL offers a rigorous set of standards that covers risk assessment for electronic products, focusing on both fire protection and electrical safety. Since their founding in 1894, UL has evolved with electronics and electrical technology, offering safety certifications for:<\/span><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><span style=\"font-weight: 400;\">The first vacuum cleaner, electrical signal system, light shield for moving pictures, and vehicle washer with electric lights in 1909. <\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">The first automatic washing machine in 1937, which had several safety hazards like water spilling into the motor. <\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">The first black and white television in 1939. UL went on to work with TV makers in 1953 to produce protective shields and glass laminates to prevent imploding picture tubes. <\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">The first video game arcade machine, microwave oven, personal computer, and solar collector between 1975 and 1980. <\/span><\/li>\n<\/ul>\n\n\n\n<p><span style=\"font-weight: 400;\">Today, UL is working on advancing safety requirements for lithium-ion batteries through computational modeling, thermal analysis, and advanced testing approaches. They&#8217;re also one of the leading certification groups to accelerate safety requirements for electric vehicle batteries. <\/span><\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full wp-image-1851\"><img loading=\"lazy\" decoding=\"async\" width=\"512\" height=\"349\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/hoverboard1-e1454513037602.jpg\" alt=\"hoverboard\" class=\"wp-image-59773\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/hoverboard1-e1454513037602.jpg 512w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/hoverboard1-e1454513037602-300x204.jpg 300w\" sizes=\"auto, (max-width: 512px) 100vw, 512px\" \/><figcaption class=\"wp-element-caption\"><em>Did we mention UL now certifies hoverboards? (<a href=\"http:\/\/www.ul.com\/newsroom\/featured\/uls-involvement-in-hoverboard-certification\/\">Image source<\/a>)<\/em><\/figcaption><\/figure>\n\n\n\n<p><span style=\"font-weight: 400;\">These days UL has a very intimate relationship with the electronics design industry. There\u2019s a very high chance that somewhere along your career journey you\u2019ll design a product that requires the UL Mark of approval.<\/span><\/p>\n\n\n<h2 class=\"wp-block-heading\" id=\"why-should-you-care-about-ul\">Why Should You Care About UL?<\/h2>\n\n\n<p><span style=\"font-weight: 400;\">Many end product standards now require their PCBs to be built with UL safety standards in mind. The following product categories are just a sample of the applications that UL standards cover:<\/span><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><span style=\"font-weight: 400;\">IEC 60065: Audio and Video Equipment<\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">IEC 60960: Information Technology Equipment<\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">IEC 60601: Medical Equipment<\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">IEC 61010: Equipment for Laboratory Use<\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">UL 508: Industrial Control Equipment<\/span><\/li>\n<\/ul>\n\n\n\n<p><span style=\"font-weight: 400;\">All of the applications above must be certified with a UL mark following three standards, UL 796, UL 746, &nbsp;and UL 94. These are broken down into specific sub-categories, which includes:<\/span><\/p>\n\n\n\n<p><b>PCB Standard UL 796<\/b><span style=\"font-weight: 400;\">. This covers printed wiring boards (PWBs) guidelines for standard rigid, metal-based, and high-density interconnect PCBs.<\/span><\/p>\n\n\n\n<p><b>PCB Standard UL 796F<\/b><span style=\"font-weight: 400;\">. This standard evolved to cover flexible material electronics including flex and rigid-flex PCBs.<\/span><\/p>\n\n\n\n<p><b>PCB Standard UL 746E<\/b><span style=\"font-weight: 400;\">. This covers all industrial laminates and materials used in the PCB manufacturing process.<\/span><\/p>\n\n\n\n<p><b>PCB Standard UL 746F<\/b><span style=\"font-weight: 400;\">. This covers all flexible dielectric film materials used in the PCB manufacturing process.<\/span><\/p>\n\n\n\n<p><b>UL 94<\/b><span style=\"font-weight: 400;\">. This covers all flammability requirements for plastics and PCBs. <\/span><\/p>\n\n\n\n<p><span style=\"font-weight: 400;\">As part of UL 796, UL 746 and UL 94 standards, PCBs are thoroughly tested under a number of conditions to evaluate the chances of electrical shock, flammability, and mechanical strength. Here\u2019s an overview of each category and the tests performed:<\/span><\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"948\" height=\"647\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-24-34.jpg\" alt=\"ul electric shock\" class=\"wp-image-59778\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-24-34.jpg 948w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-24-34-300x205.jpg 300w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-24-34-768x524.jpg 768w\" sizes=\"auto, (max-width: 948px) 100vw, 948px\" \/><\/figure>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"968\" height=\"621\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-25-33.jpg\" alt=\"ul flammability\" class=\"wp-image-59783\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-25-33.jpg 968w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-25-33-300x192.jpg 300w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-25-33-768x493.jpg 768w\" sizes=\"auto, (max-width: 968px) 100vw, 968px\" \/><\/figure>\n\n\n\n<ul class=\"wp-block-list\">\n<li><span style=\"font-weight: 400;\">MOT \u2013 Maximum Operating Temperature<\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">DSR \u2013 Direct Support Requirement <\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">RTI \u2013 Relative Thermal Index<\/span><\/li>\n<\/ul>\n\n\n\n<p><span style=\"font-weight: 400;\">Aside from verifying the safety of your electronic device, UL certification also offers other benefits to end users and the industry as a whole, including:<\/span><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><b>Reach<\/b><span style=\"font-weight: 400;\">. UL certified PCBs are recognized globally and can help to extend the reach of your product to new markets. <\/span><\/li>\n\n\n\n<li><b>Standardization<\/b><span style=\"font-weight: 400;\">. PCB manufacturers can work from a common set of guidelines to help standardize the fabrication and assembly process.<\/span><\/li>\n\n\n\n<li><b>Trust<\/b>. End users and consumers are provided a product that meets a rigorous set of safety standards.<\/li>\n<\/ul>\n\n\n<h2 class=\"wp-block-heading\" id=\"types-of-ul-pcb-certifications\">Types of UL PCB Certifications<\/h2>\n\n\n<p><span style=\"font-weight: 400;\">UL certifies PCBs under a PCB Recognition Program that comes in two flavors &#8211; Full Recognition and Flame-Only Recognition. These break down to meet the following requirements:<\/span><\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full wp-image-1854\"><img loading=\"lazy\" decoding=\"async\" width=\"938\" height=\"427\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-32-14.jpg\" alt=\"types of pcb recognition\" class=\"wp-image-59788\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-32-14.jpg 938w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-32-14-300x137.jpg 300w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-32-14-768x350.jpg 768w\" sizes=\"auto, (max-width: 938px) 100vw, 938px\" \/><figcaption class=\"wp-element-caption\"><em>Types of PCB Recognition offered by UL. (<a href=\"https:\/\/www.ncabgroup.com\/wp-content\/uploads\/2015\/03\/UL-Emma-Hudson-NCAB-Seminar-2015-03.pdf\">Image source<\/a>)<\/em><\/figcaption><\/figure>\n\n\n<h3 class=\"wp-block-heading\" id=\"flame-ratings\">Flame Ratings<\/h3>\n\n\n<p><span style=\"font-weight: 400;\">Flame ratings are typically specified by end product requirements and evaluate a sample burn time when a PCB is subjected to a horizontal and vertical flame. These flames are broken down into classes, which includes V-0, V-1, V2, VTM-0, VTM-1, and VTM-2. Details on measured conditions for each class are shown below:<\/span><\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-large size-full wp-image-1855\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"568\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-34-08-1024x568.jpg\" alt=\"ul flame rating classification\" class=\"wp-image-59793\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-34-08-1024x568.jpg 1024w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-34-08-300x166.jpg 300w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-34-08-768x426.jpg 768w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-34-08.jpg 1116w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\"><em>UL flame rating classifications are broken down by criteria. (<a href=\"https:\/\/www.ncabgroup.com\/wp-content\/uploads\/2015\/03\/UL-Emma-Hudson-NCAB-Seminar-2015-03.pdf\">Image source<\/a>)<\/em><\/figcaption><\/figure>\n\n\n<h3 class=\"wp-block-heading\" id=\"solder-limits\">Solder Limits<\/h3>\n\n\n<p><span style=\"font-weight: 400;\">Solder limits test the kind of soldering processes that a PCB will be subjected to during the component assembly process. These tests simulate a thermal shock and maximum temperature to gauge how your PCB performs. <\/span><\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full wp-image-1856\"><img loading=\"lazy\" decoding=\"async\" width=\"700\" height=\"239\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/con08_01.jpg\" alt=\"ul thermal shock\" class=\"wp-image-59798\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/con08_01.jpg 700w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/con08_01-300x102.jpg 300w\" sizes=\"auto, (max-width: 700px) 100vw, 700px\" \/><figcaption class=\"wp-element-caption\"><em>An example of how thermal shock is applied to solder, notice the cracks. (<a href=\"https:\/\/product.tdk.com\/info\/en\/techlibrary\/archives\/techjournal\/vol05_mlcc\/contents08.html\">Image source<\/a>)<\/em><\/figcaption><\/figure>\n\n\n<h3 class=\"wp-block-heading\" id=\"maximum-operating-temperature\">Maximum Operating Temperature<\/h3>\n\n\n<p><span style=\"font-weight: 400;\">Maximum Operating Temperature (MOT) defines a PCBs maximum continuous use at a specific temperature. This test simulates the exposure of a PCB to normal operating condition temperatures during a 10-56 day period, with temperatures based on your manufacturer\u2019s guidelines. <\/span><\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"direct-support-request\">Direct Support Request<\/h3>\n\n\n<p><span style=\"font-weight: 400;\">Direct Support Request (DSR) measures the performance of a PCB laminate when in contact with 120V or less. This test is only performed on laminates rather than the whole PCB, and each laminate receives a DSR compliant rating. During this testing, a laminate will undergo several performance tests, including:<\/span><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><span style=\"font-weight: 400;\">Dielectric strength<\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">High current arc ignition<\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">Hot wire ignition<\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">Volume resistivity<\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">Heat deflection<\/span><\/li>\n<\/ul>\n\n\n<h3 class=\"wp-block-heading\" id=\"comparative-tracking-index\">Comparative Tracking Index<\/h3>\n\n\n<p><span style=\"font-weight: 400;\">The Comparative Tracking Index (CTI) also measures the performance of a PCB laminate materials when subjected to a wet contaminant. CTI values are listed as Performance Level Categories (PLC) as shown in the table below:<\/span><\/p>\n\n\n<?xml encoding=\"utf-8\" ?><figure class=\"wp-block-table MuiTableContainer-root\"><table class=\" MuiTable-root DhigTable--verticalAlignment--top\"><tbody><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\"><b>CTI range&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<\/b><\/td><td class=\" MuiTableCell-root\"><b>PLC class&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<\/b><\/td><\/tr><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\">\n<p style=\"text-align: center;\"><span style=\"font-weight: 400;\">&ge; 600<\/span><\/p>\n<\/td><td class=\" MuiTableCell-root\">\n<p style=\"text-align: center;\"><span style=\"font-weight: 400;\">0<\/span><\/p>\n<\/td><\/tr><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\">\n<p style=\"text-align: center;\"><span style=\"font-weight: 400;\">400 &#10135; 599<\/span><\/p>\n<\/td><td class=\" MuiTableCell-root\"><span style=\"font-weight: 400;\">1<\/span><\/td><\/tr><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\"><span style=\"font-weight: 400;\">250 &#10135; 399<\/span><\/td><td class=\" MuiTableCell-root\">\n<p style=\"text-align: center;\"><span style=\"font-weight: 400;\">2<\/span><\/p>\n<\/td><\/tr><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\">\n<p style=\"text-align: center;\"><span style=\"font-weight: 400;\">175 &#10135; 249<\/span><\/p>\n<\/td><td class=\" MuiTableCell-root\">\n<p style=\"text-align: center;\"><span style=\"font-weight: 400;\">3<\/span><\/p>\n<\/td><\/tr><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\"><span style=\"font-weight: 400;\">100 &#10135; 174<\/span><\/td><td class=\" MuiTableCell-root\">\n<p style=\"text-align: center;\"><span style=\"font-weight: 400;\">4<\/span><\/p>\n<\/td><\/tr><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\"><span style=\"font-weight: 400;\">&lt; 100<\/span><\/td><td class=\" MuiTableCell-root\">\n<p style=\"text-align: center;\"><span style=\"font-weight: 400;\">5<\/span><\/p>\n<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p><span style=\"font-weight: 400;\">In addition to Full-Recognition and Flame-Only Recognition, PCBs are broken down by category to identify UL-specific requirements based on construction type. These types include:<\/span><\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"single-layer-pcbs\">Single Layer PCBs<\/h3>\n\n<?xml encoding=\"utf-8\" ?><figure class=\"wp-block-table MuiTableContainer-root\"><table class=\" MuiTable-root DhigTable--verticalAlignment--top\"><tbody><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\"><b>Full Recognition Requirements<\/b><\/td><td class=\" MuiTableCell-root\"><b>Flame-Only Recognition Requirements<\/b><\/td><\/tr><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\">\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum laminate thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum starting copper foil thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Single or double-sided boards<\/span><\/li>\n<\/ul>\n<\/td><td class=\" MuiTableCell-root\">\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum laminate thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Single or double-sided boards<\/span><\/li>\n<\/ul>\n<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"622\" height=\"214\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-42-45.jpg\" alt=\"single layer pcb stackup\" class=\"wp-image-59803\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-42-45.jpg 622w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-42-45-300x103.jpg 300w\" sizes=\"auto, (max-width: 622px) 100vw, 622px\" \/><\/figure>\n\n\n<h3 class=\"wp-block-heading\" id=\"multi-layer-pcbs\">Multi Layer PCBs<\/h3>\n\n<?xml encoding=\"utf-8\" ?><figure class=\"wp-block-table MuiTableContainer-root\"><table class=\" MuiTable-root DhigTable--verticalAlignment--top\"><tbody><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\"><b>Full Recognition Requirements<\/b><\/td><td class=\" MuiTableCell-root\"><b>Flame-Only Recognition Requirements<\/b><\/td><\/tr><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\">\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum dielectric build-up thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum laminate and prepreg sheet thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum starting external copper foil thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Maximum internal copper thickness<\/span><\/li>\n<\/ul>\n<\/td><td class=\" MuiTableCell-root\">\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum dielectric build-up thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum laminate and prepreg sheet thickness<\/span><\/li>\n<\/ul>\n<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"908\" height=\"247\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-43-12.jpg\" alt=\"multilayer pcb stackup\" class=\"wp-image-59808\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-43-12.jpg 908w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-43-12-300x82.jpg 300w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-43-12-768x209.jpg 768w\" sizes=\"auto, (max-width: 908px) 100vw, 908px\" \/><\/figure>\n\n\n<h3 class=\"wp-block-heading\" id=\"metal-base-single-layer-pcbs\">Metal Base, Single Layer PCBs<\/h3>\n\n<?xml encoding=\"utf-8\" ?><figure class=\"wp-block-table MuiTableContainer-root\"><table class=\" MuiTable-root DhigTable--verticalAlignment--top\"><tbody><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\"><b>Full Recognition Requirements<\/b><\/td><td class=\" MuiTableCell-root\"><b>Flame-Only Recognition Requirements<\/b><\/td><\/tr><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\">\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum and maximum dielectric thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum metal thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum starting copper foil thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Single or double-sided boards<\/span><\/li>\n<\/ul>\n<\/td><td class=\" MuiTableCell-root\">\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum and maximum dielectric thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum metal thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Single or double-sided boards<\/span><\/li>\n<\/ul>\n<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"991\" height=\"206\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-43-49.jpg\" alt=\"metal base single layer pcb\" class=\"wp-image-59813\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-43-49.jpg 991w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-43-49-300x62.jpg 300w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-43-49-768x160.jpg 768w\" sizes=\"auto, (max-width: 991px) 100vw, 991px\" \/><\/figure>\n\n\n<h3 class=\"wp-block-heading\" id=\"metal-base-multi-layer-pcbs\">Metal Base, Multi Layer PCBs<\/h3>\n\n<?xml encoding=\"utf-8\" ?><figure class=\"wp-block-table MuiTableContainer-root\"><table class=\" MuiTable-root DhigTable--verticalAlignment--top\"><tbody><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\"><b>Full Recognition Requirements<\/b><\/td><td class=\" MuiTableCell-root\"><b>Flame-Only Recognition Requirements<\/b><\/td><\/tr><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\">\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum and maximum dielectric build-up thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum individual sheet thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum starting external copper foil thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Maximum internal copper foil thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum metal thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Single or double-sided boards<\/span><\/li>\n<\/ul>\n<\/td><td class=\" MuiTableCell-root\">\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum and maximum dielectric build-up thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum laminate and prepreg sheet thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum metal thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Single or double-sided boards<\/span><\/li>\n<\/ul>\n<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"938\" height=\"264\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-44-59.jpg\" alt=\"metal base multi layer pcb\" class=\"wp-image-59818\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-44-59.jpg 938w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-44-59-300x84.jpg 300w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-44-59-768x216.jpg 768w\" sizes=\"auto, (max-width: 938px) 100vw, 938px\" \/><\/figure>\n\n\n<h3 class=\"wp-block-heading\" id=\"high-density-interconnect-pcbs\">High Density Interconnect PCBs<\/h3>\n\n<?xml encoding=\"utf-8\" ?><figure class=\"wp-block-table MuiTableContainer-root\"><table class=\" MuiTable-root DhigTable--verticalAlignment--top\"><tbody><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\"><b>Full Recognition Requirements<\/b><\/td><td class=\" MuiTableCell-root\"><b>Flame-Only Recognition Requirements<\/b><\/td><\/tr><tr class=\" MuiTableRow-root\"><td class=\" MuiTableCell-root\"><span style=\"font-weight: 400;\">Core Requirements<\/span>\n<p>&nbsp;<\/p>\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum dielectric build-up thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum laminate and prepreg sheet thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum eternal copper foil thickness when no HDI material is applied<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Maximum internal copper thickness<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">HDI Requirements<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum and maximum HDI layer thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum and maximum number of HDI layers applied<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Maximum internal copper thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum external copper foil thickness<\/span><\/li>\n<\/ul>\n<\/td><td class=\" MuiTableCell-root\"><span style=\"font-weight: 400;\">Core Requirements<\/span>\n<p>&nbsp;<\/p>\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum dielectric build-up thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum laminate and prepreg sheet thickness<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">HDI Requirements<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum and maximum HDI layer thickness<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Minimum and maximum number of HDI layers applied<\/span><\/li>\n<\/ul>\n<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<figure class=\"wp-block-image aligncenter size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"349\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-45-28-1024x349.jpg\" alt=\"high density interconnect pcb\" class=\"wp-image-59823\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-45-28-1024x349.jpg 1024w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-45-28-300x102.jpg 300w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-45-28-768x262.jpg 768w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-45-28.jpg 1167w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n<h3 class=\"wp-block-heading\" id=\"flexible-pcbs\">Flexible PCBs<\/h3>\n\n\n<p><span style=\"font-weight: 400;\">Flexible PCBs are defined by both their application type and construction type. You can reference the above tables for a flexible PCB construction type with the following application parameters:<\/span><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><b>Flexible PCBs<\/b><span style=\"font-weight: 400;\"> are tested for dynamic and repeated bending. <\/span><\/li>\n\n\n\n<li><b>Flex-to-Install PCBs<\/b><span style=\"font-weight: 400;\"> are tested for flexing during installation and field servicing.<\/span><\/li>\n\n\n\n<li><b>Rigid-Flex PCBs<\/b> are assessed for a variety of applications, and construction types gave their combination of flexible and rigid circuitry.<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"853\" height=\"306\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-46-17.jpg\" alt=\"flexible pcb\" class=\"wp-image-59828\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-46-17.jpg 853w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-46-17-300x108.jpg 300w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-46-17-768x276.jpg 768w\" sizes=\"auto, (max-width: 853px) 100vw, 853px\" \/><\/figure>\n\n\n<h2 class=\"wp-block-heading\" id=\"what-does-the-ul-mark-mean-on-a-pcb\">What Does the UL Mark Mean On a PCB?<\/h2>\n\n\n<p><span style=\"font-weight: 400;\">When your PCB receives a UL Mark from your manufacturer, it signifies that your board meets all established safety and flammability requirements. Specifically, a UL Mark signifies that:<\/span><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><span style=\"font-weight: 400;\">The base material used in your PCB meets a specified flammability level per UL94. For example, when FR4 is subjected to an open flame and then removed it self-extinguishes within 10 seconds and does not drip any flaming particles. Each base material that a manufacturer offers will go through this testing scenario. <\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">The base material used in your PCB meets the required level of ability to resist ignition from external electrical sources. <\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">The base material used in your PCB meets the required electrical breakdown value. This is the voltage difference where the insulation properties of a base material may start to break down and cause safety issues. <\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">The base material in your PCB meets the performance levels for direct support of current carrying capacities as specified in UL 796A. <\/span><\/li>\n<\/ul>\n\n\n\n<p><span style=\"font-weight: 400;\">When your PCB receives its UL Mark, it will be printed on your silkscreen layer as shown in the image below. In this example, UL94V-0 signifies that this board meets UL94 flammability requirements at flame class V-0. The E198312 is a unique UL Mark identifier for a specific manufacturer, and ML signifies that this is a Multi-Layer PCB. <\/span><\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full wp-image-1864\"><img loading=\"lazy\" decoding=\"async\" width=\"207\" height=\"143\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/leiterplatten_ul-zertifiziert.jpg\" alt=\"example ul mark\" class=\"wp-image-59833\"\/><figcaption class=\"wp-element-caption\"><em>Example UL Mark on a PCB. (<a href=\"https:\/\/www.multi-circuit-boards.eu\/en\/printed-circuit-quality\/ul-certification.html\">Image source<\/a>)<\/em><\/figcaption><\/figure>\n\n\n<h2 class=\"wp-block-heading\" id=\"how-does-ul-affect-my-job-as-a-pcb-designer\">How Does UL Affect My Job as a PCB Designer?<\/h2>\n\n\n<p><span style=\"font-weight: 400;\">UL certification is driven by the end product requirements, and it\u2019s up to you as the PCB designer to know and understand these requirements. We recommend first checking with your end product manufacturer before beginning your design process to determine the specific requirements your PCB must meet. If you are designing any of the UL specified products below then you\u2019ll likely need to get your hands on <\/span><a href=\"https:\/\/standardscatalog.ul.com\/\"><span style=\"font-weight: 400;\">UL standards documentation<\/span><\/a><span style=\"font-weight: 400;\">:<\/span><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><span style=\"font-weight: 400;\">UL 60950 \u2013 Information Technology Equipment<\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">UL 60065 \u2013 Audio &amp; Video Equipment<\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">UL 62368 \u2013 ITE and Audio\/Video Equipment<\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">UL 60601 \u2013 Medical Equipment<\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">UL 60335 \u2013 Appliances<\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">UL 61010 \u2013 Industrial Control Equipment<\/span><\/li>\n\n\n\n<li><span style=\"font-weight: 400;\">UL 8750 \u2013 LED Equipment<\/span><\/li>\n<\/ul>\n\n\n\n<p><span style=\"font-weight: 400;\">Once you know your end product rating requirements, it\u2019s time to get started on your design. There are several things to keep in mind when designing a board for UL, including:<\/span><\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"always-select-ul-certified-parts\">Always Select UL Certified Parts<\/h3>\n\n\n<p><span style=\"font-weight: 400;\">Make sure you always use UL listed parts whenever you have a line voltage present in your design as this will reduce the cost of certification. If you don\u2019t select UL listed parts from your distributor, then someone down the line will have to do the investigation and adjustments. Instead of risking a delay for your project, be sure to look for UL certification marks when putting together your component list. You might need to dig into the datasheet for each component to find the UL approval, as shown for this Metal-Oxide Varistor below:<\/span><\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full wp-image-1865\"><img loading=\"lazy\" decoding=\"async\" width=\"1016\" height=\"870\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-49-49.jpg\" alt=\"ul certified parts\" class=\"wp-image-59838\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-49-49.jpg 1016w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-49-49-300x257.jpg 300w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/2017-10-27_16-49-49-768x658.jpg 768w\" sizes=\"auto, (max-width: 1016px) 100vw, 1016px\" \/><figcaption class=\"wp-element-caption\"><em>Finding the UL approval for components can take some datasheet investigation. (<a href=\"http:\/\/www.farnell.com\/datasheets\/2243464.pdf?_ga=2.144754932.1769514290.1505412004-1605871118.1505321165\">Image source<\/a>)<\/em><\/figcaption><\/figure>\n\n\n<h3 class=\"wp-block-heading\" id=\"follow-clearance-and-creepage-distances-on-your-board-layout\">Follow Clearance and Creepage Distances On Your Board Layout<\/h3>\n\n\n<p><span style=\"font-weight: 400;\">For high voltage design with operating voltages between 30VAC and 60vDC, you\u2019ll need to pay particular attention to your clearances and creepage when setting up your design rules. There is some confusion between these two rules. Most design tools, including EAGLE, categorize both creepage and clearance rules under a general Clearance category. However, there\u2019s an important distinction to make between both:<\/span><\/p>\n\n\n\n<p><span style=\"font-weight: 400;\">Rules for pad-to-pad, pad-to-trace, or trace-to-trace, spacing are considered <\/span><b>creepage<\/b><span style=\"font-weight: 400;\"> rules. These rules define the shortest path between two conductive parts.<\/span><\/p>\n\n\n\n<p><span style=\"font-weight: 400;\">Rules that define the spacing between two conductive elements measured through the air are considered <\/span><b>clearance<\/b><span style=\"font-weight: 400;\"> rules.<\/span><\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full wp-image-1866\"><img loading=\"lazy\" decoding=\"async\" width=\"452\" height=\"600\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/1-1.png\" alt=\"clearance and creepage\" class=\"wp-image-59843\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/1-1.png 452w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/1-1-226x300.png 226w\" sizes=\"auto, (max-width: 452px) 100vw, 452px\" \/><figcaption class=\"wp-element-caption\"><em>The difference between clearance and creepage per IEC guidelines. (<a href=\"http:\/\/blog.optimumdesign.com\/clearance-and-creepage-rules-for-pcb-assembly\">Image source<\/a>)<\/em><\/figcaption><\/figure>\n\n\n\n<p><span style=\"font-weight: 400;\">Clearance and creepage requirements will be determined by your specific design requirements, and there are no general rules to offer here. Instead, be sure to use this <\/span><a href=\"http:\/\/www.creepage.com\/\"><span style=\"font-weight: 400;\">Creepage and Clearance Calculator<\/span><\/a><span style=\"font-weight: 400;\"> which meets specifications for UL 60950 and UL 60960-1 among other popular IEC guidelines.<\/span><\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"specify-dielectric-materials-for-your-manufacturer\">Specify Dielectric Materials for Your Manufacturer<\/h3>\n\n\n<p><span style=\"font-weight: 400;\">For some end products, UL certification can take weeks or months to secure as your device goes through a series of qualifying tests. Instead of allowing your manufacturer to select any fiberglass material, be sure to specify your dielectric material requires in your design documentation. This will help to avoid any delays in your certification process and costly respins.<\/span><\/p>\n\n\n<h3 class=\"wp-block-heading\" id=\"getting-your-ul-marking\">Getting Your UL Marking<\/h3>\n\n\n<p><span style=\"font-weight: 400;\">The good news is that getting a UL Marking on a PCB is a relatively straightforward process. The bulk of UL requirements rest on the shoulders of your manufacturer as part of a UL compliance program. Under this program, your manufacturer is audited for UL compliance four times per year. For manufacturers producing Full Recognition PCBs, random production boards will also be subject to annual testing.<\/span><\/p>\n\n\n\n<p><span style=\"font-weight: 400;\">When getting a quote for the fabrication of your PCB most manufacturer websites will have a section where you can select your needs for a UL Marking. In the image below we were able to add a UL Mark through the pcb.cart.com quote tool.<\/span><\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"838\" height=\"488\" src=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/pcbcart-ulmarking.jpg\" alt=\"pcbcart ulmarking\" class=\"wp-image-59848\" srcset=\"https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/pcbcart-ulmarking.jpg 838w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/pcbcart-ulmarking-300x175.jpg 300w, https:\/\/www.autodesk.com\/products\/fusion-360\/blog\/wp-content\/uploads\/2023\/07\/pcbcart-ulmarking-768x447.jpg 768w\" sizes=\"auto, (max-width: 838px) 100vw, 838px\" \/><\/figure>\n\n\n<h2 class=\"wp-block-heading\" id=\"safety-first\">Safety First<\/h2>\n\n\n<p><span style=\"font-weight: 400;\">Whether you\u2019re designing medical equipment, an IT device, or even a PCB for an appliance, chances are you\u2019ll need to have your board UL certified. The bulk of the certification process is already handled by your manufacturer as they work with UL to test materials and components. However, as a PCB designer, you still need to take the time to research and define the requirements of your circuit board to meet your end product needs. Once your requirements are defined, you\u2019ll need to select UL certified parts during your schematic design and follow creepage and clearance distances on your board layout. Most importantly, when documenting your board, it\u2019s critical to specify the right dielectric material that will meet your end product requirements.<\/span><\/p>\n\n\n\n<p><span style=\"font-weight: 400;\">Ready to design your first UL recognized PCB? <\/span><a href=\"https:\/\/www.autodesk.com\/products\/eagle\/subscribe?plc=EGLSTD&amp;term=1-YEAR&amp;support=BASIC&amp;quantity=1\"><span style=\"font-weight: 400;\">Subscribe to Autodesk EAGLE today!<\/span><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Need a stamp of safety for your upcoming electronics project? Learn what you need to know about UL certification as an electronics designer. <\/p>\n","protected":false},"author":2425,"featured_media":440,"menu_order":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":""},"categories":[434,286],"tags":[],"coauthors":[],"class_list":["post-18007","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-eagle","category-eda","dhig-theme--light"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.3 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>UL Certification Electronics Design | EAGLE | Blog<\/title>\n<meta name=\"description\" content=\"Learn what you need to know about UL certification for PCB design, including UL 796 PCB standards and UL 94 PCB flammability and fire safety.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, 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