Everything you need to know about safety testing and certification

Oct. 9, 2003
What does it take to get a product safety certified and qualified to carry an approval mark?
Consumer products, such as these water heaters, are rigorously tested before being certified as meeting safety and performance standards.
Standards development and the certification process
Developers create standards which are used by manufacturers and T&C labs to certify products for the marketplace.

Sandudhir Joshi
Manager of Certification Business Development, Analytical, and Electronic Products

Trig Smith
Manager of Certification Business Development, Control, Distribution, and Industrial Equipment

CSA International
Toronto, Ontario, Canada

Whether you design industrial equipment or the latest consumer products, testing and certification (T&C) can be crucial to the overall success of your product in the marketplace. It shows customers your design meets all applicable standards.

It isn't always obvious, but designers usually have several options in selecting a T&C lab. By comparing different agencies' service, cost, and other factors, designers can get new products to market sooner and with lower T&C expenses. Understanding the T&C process and following a few tips described here, they can avoid some common problems.

Marks of approval

Independent, accredited testing labs license manufacturers to put approval marks on qualifying products. To qualify, products must pass rigorous, carefully controlled testing that determines if they meet applicable standards.

Much of the confusion about approval marks stems from not understanding the differences between testing labs and standards publishers. In some cases, one organization does both, and so a standard may bear the name of a publishing company (for example, UL standard 507 for electric fans, or CSA standard Z21.47/CSA 2.3 for gas-fired central furnaces). This leads to the mistaken belief products must be tested and certified by the company whose name graces the standard. The truth is, any accredited testing lab can test and certify products against any standards, regardless of who publishes them.

Check the accreditation

T&C labs must be properly accredited to qualify for product testing. Accreditation means the lab has the capabilities, control programs, independence, and the reporting and complaint-handling procedures. The Occupational Safety and Health Administration (OSHA) accredits labs to check electrical, gas, and other products against U.S. standards. OSHA-accredited facilities are known as Nationally Recognized Testing Labs (NRTLs).

To be accredited, U.S. labs must apply to OSHA which checks the application and conducts an on-site review of the lab's organization, programs, and test facilities. Preliminary findings are published in the Federal Register to allow public comment. Following a waiting period, OSHA publishes a second notification and responds to any comments. With successful applications, the second notice signifies the lab is now an NRTL. CSA International and Underwriters Labs are examples of OSHA NRTLs.

All NRTLs test against the same standards, regardless of who wrote or published them. So if two labs are both NRTLs for electrical motors, a motor certified by one lab meets the same criteria as a motor tested by the other.

In addition to OSHA, other bodies accredit labs as qualified to test electrical, gas, and other classes of products for the U.S. market. They include American National Standards Institute (ANSI), the International Council of Building Officials (ICBO), the National Voluntary Lab Accreditation Program (NVLAP), the American Society of Safety Engineers (ASSE), and National Evaluation Services (NES).

Several labs are accredited to test and certify various products. Therefore, manufacturers have the freedom and flexibility to select among them based on timing, cost, convenience, and other considerations for particular certification projects. This helps eliminate potential bottlenecks in bringing new products to market.

The road to certification

When new products are ready for T&C, manufacturers often request estimates from one or more labs. Manufacturers should compare estimates and select labs based on cost, time constraints, customer service, and other relevant criteria.

The T&C agency will need samples of the completed product and data such as the list of materials used, schematics, and component information. A little extra work at this stage often saves time and money down the road. For example, a submission that covers all anticipated variants of a product is more efficient and less expensive than making multiple submissions. Similarly, anticipating where different components or alternative materials may be used can prevent resubmitting or requalifying designs later.

If the product satisfies all requirements, the T&C lab provides written confirmation -- a certification report and Certificate of Compliance. The product is considered certified and is listed in the agency's directory. Directories are often available online for verifying particular products are certified. If manufacturers want to put the certification mark on their products, however, they must negotiate licensing agreements with the testing agency.

Those designing and manufacturing new devices and products should be mindful of germane U.S., Canadian, and international standards. If you have specific questions about how standards affect your product, contact a certification agency. Don't wait until you are about to submit the product for certification to bring up concerns. Here are other tips that can ease the T&C process:

  • When requesting estimates from a T&C lab, first tell them what the product is, what it does, what it looks like, and the countries and environments it will be used in. Send a photo, if possible, along with a list of components, materials, and possible alternative components and materials that will be used in the product. Be sure to include the manufacturer's name, model, and catalog number, and, if applicable, its electrical rating, wiring diagrams, and certification agency file number. Companies should also send model and catalog numbers that will be covered by certification and similarities between different models, as well as the full names, addresses, and a contact person at all of facilities assembling the product.
  • Product testing can be performed at a manufacturer's facilities, eliminating the time and expense of shipping. However, a T&C lab must first ensure the manufacturer's staff understands applicable standards and tests and that proper testing equipment is available and calibrated. T&C labs often provide templates that let manufacturers' testers prepare certification drafts, which saves time.
  • Understand applicable standards before starting production. Manufacturers familiar with standards can make sure assembly is done correctly and with proper components. Knowing the standards also eliminates confusion regarding test results.
  • Ensure electrical schematics and other drawings are current. Drawings that aren't up to date may not match samples submitted for testing, causing delays. To further reduce delays, send drawings and photos electronically. It is the fastest way to submit them. But when sending images electronically, ensure the testing lab's software works with your files.
  • Samples submitted for testing should be identical to the final versions that will be manufactured. In one case, a manufacturer submitted a sample controller for testing. But just before the sample was sent out, the manufacturer said the final version would "not be exactly the same." This statement could mean minor cosmetic tweaks or major design changes. In this instance, the company meant that the controller's circuit board was being changed, which is a major change. T&C was delayed while the new circuit board was examined for compliance.
  • Some labs offer services and programs that speed up certification. For example, CSA International's Technical Information Service has certification experts that evaluate designs before manufacturers formally submit them for T&C. This is particularly useful for new designs and technologies which are not obviously covered by existing standards or if certification is new to the manufacturer.

Who's who in T&C

Three different groups participate in product testing and certification: manufacturers, standards developers, and T&C labs.

Product manufacturers design and make products that need to be certified.

Standards developers are often set up as technical committees that include representatives from government, industry, consumers, and end-users. They develop standards for particular product classes and work with standard publishers. In the U.S., developers commonly delegate the publishing, maintenance, and distribution of standards to organizations such as ANSI, ASTM, CSA America, NSF, and UL.

T&C labs are independent agencies hired by manufacturers. They test products and certify that they meet applicable standards. In some cases, such as the CSA, NSF, and UL, the same company has standard publishers and T&C labs. This has led to so-called "CSA standards," "NSF standards," and "UL standards." But in all three of these examples, each standard is available to any accredited testing labs for use in T&C.

Organizations that publish standards and certify products do so separately and independently. Within the CSA Group, for example, CSA America publishes U.S. standards, while CSA International handles T&C in North American.


What the marks mean

Approval marks provide a visible indication that a product or component meets applicable standards for safety and performance. Examples of some issued by accredited testing labs and common on U.S. products include CSA, UL, NSF, ETL, and TUV. While a few appear on a range of products, others are issued for specific classes of products or products designed for particular geographic regions.

A few examples of marks from CSA International and explanations of when they are used.

The CSA US mark indicates that a product meets applicable U.S. standards, including those from ANSI, ASME, ASSE, ASTM, NSF, and UL.

The CSA C/US mark signifies that the product meets applicable U.S. and Canadian standards, including those from CSA, ANSI, ASME, ASSE, ASTM, NSF, and UL.

The CSA Blue Star, found on gas-fired products, demonstrates that they meet U.S. standards for gas-fired products published by ANSI and CSA.

A glossary of T&C acronyms

ANSI: American National Standards Institute
ASSE: American Society of Sanitary Engineers
ASTM International: American Society for Testing and MaterialsCSA: Canadian Standards Assoc.
ETL: Electrical Testing Laboratories. The ETL mark now belongs to ETL Semko, a division of Intertek Testing Services. (www.etlsemko.com)
NSF: National Sanitation Foundation
TUV: Technischer Ueberwahungsverein, or Technical Inspection Assoc., is part of TUV Rhineland of North America www.us.tuv.com

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