The testing and sourcing of UL, cUL and CSA approved label constructions can be complicated. Not providing the right details to your supplier up front can prevent them from providing an accurate quote or could delay the delivery of your parts. At its worst, lack of compliance could shut down your production line.
Most certified products are required to be permanently marked with specific safety-related information such as hazards, warnings, cautionary markings, installation instructions, electrical ratings, etc. The labels that contain this information typically require UL/CSA approval for your product to be in compliance.
These agencies are testing to ensure that label parts will not fail to adhere or become illegible in the environments and under the conditions for which they are intended to be used, over the life of the product.
To ensure compliance, it is critical that you provide the right specifications to your supplier. You need to tell them about the environment to which your label will be exposed (including temperature ranges, humidity levels, chemical splashes, etc.) and the surface to which it will be applied. For example, a part exposed to gasoline splashing, used on a lawnmower or marine engine, could require a subsurface printed film or an overlaminated film. If the same label will be used on multiple surfaces – from aluminum to glass to epoxy-powder paint – the adhesive specified must work well on each surface. Here are the most common specifications that must be shared:
• Hottest and coldest temperatures
• Indoor or outdoor use
• Humidity levels
• Chemical splashes
• Length of exposure (e.g., product lifetime)
• Product surface
• Secondary printing
Labels intended to receive additional printing by the end-use manufacturer are often sold in bulk as blank labels or have blank areas on preprinted labels. Inks for which these labels have been found to be compatible are listed on UL’s Recognition Card. Overlamination materials under this category will need further evaluation, however.
Be sure to inform your supplier whether you will be adding secondary printing to the label; if it will be done with a ribbon or toner; if the ribbon is thermal transfer wax, resin or wax/resin; and whether you will use a dot matrix or laser printer. This will help them determine what type of topcoating may be required.
If your product is sold in the U.S., then UL 969 Test Standard applies.
If it’s sold in Canada, then CSA C22.2 No. 0.15-15 Test Standard applies. Whether your product was tested by UL for their Canadian cUL or by CSA, the same CSA C22.2 No. 0.15-15 Test Standard applies.
UL has different categories for evaluating label parts based on their end-use application. For example, the UL categories for marking and label systems are:
• Finished labels made by a label printer/converter (Category Code Number PGDQ2)
• Printed and unprinted labels that will receive additional printing by the end-use product manufacturer (usually using thermal transfer, laser, hot stamping or other method) (CCN PDJI2)
• In-mold labels that are embedded in a plastic part (CCN PGIM2)
• Labels, cord tags and placards that have been evaluated for specific limited uses (CCN PGIS2)
There are also standards for the various components that go into making labels, including blank stock, laminating adhesives and overlaminations. (CCN PGGU2)
Yes, through UL’s Label Adoption process. This program allows label printers and converters to demonstrate that their labels have been evaluated to meet UL safety requirements. By working with a supplier whose label constructions and/or materials have already been approved for a specified end use, you can speed up the sourcing process and reduce your expense. Conditions of Acceptability are published by UL in the agency’s online certification directory, now called Product iQ.
Inks are not directly covered under the Marking & Labeling System Materials Recognition program. However, some label material manufacturers have submitted their materials to UL with printing on them to determine the compatibility of specific flexographic, screen printing and other inks. The benefit of such print testing can be passed along to the label printer with the initial label certification if requested.
UL promotes pre-selection of labels and label suppliers via its iQ™ databases. You can search UL iQ by company name, country location, file number, model/system designation, surface type, temperature, special conditions, uses and exposures, or trade name. This is a way to find all suitable labels that meet your selected search criteria.
UL Verification Services provides customized performance and verification testing of labels or label materials based on your specific requirements. They have the technical expertise and testing capabilities to check markings and labels, verify physical constructions, and test performance under various environmental conditions.
To learn more, visit these websites:
A qualified UL label supplier can also help you with these unique situations. They can be your liaison to UL and help ensure your labels are compliant, no matter how complex or unique your situation is.
A good label supplier also will ensure you have access to strategic partnerships for in-house innovation and the best materials for your applications. They should continually evaluate your program and come to you with the appropriate UL solutions already in place.