The National Electrical Code’s Section 90.7, Examination of Equipment for Safety, is possibly one of the greatest timesaving tools electrical inspectors have at their disposal.
The intent of NEC 90.7 is to relieve inspectors of the burden of performing field inspections on factory-installed internal wiring or equipment construction at the time it’s installed. Section 90.7 states that "For specific items of equipment and materials referred to in this Code, examinations for safety made under standard conditions will provide a basis for approval where the record is generally available through promulgation by organizations properly equipped and qualified for experimental testing, inspections of the run of goods at factories, and service-value determination through field inspections. This avoids the necessity for repetition of examinations by different examiners, frequently with inadequate facilities for such work, and the confusion that would result from conflicting reports as to the suitability of devices and materials examined for a given purpose. It is the intent of this Code that factory-installed internal wiring or the construction of equipment need not be inspected at the time of installation of the equipment, except to detect alterations or damage, if the equipment has been listed by a qualified electrical testing laboratory that is recognized as having the facilities described above and that requires suitability for installation in accordance with this Code.”
Identifying Listed Products
Article 100 of the NEC provides the following definition for the term "listed”: "Equipment, materials, or services included in a list published by an organization that is acceptable to the authority having jurisdiction and concerned with evaluation of product or services, that maintains periodic inspection of production of listed equipment or materials, or periodic evaluation of services, and whose listing states that the equipment, material or services, either meets appropriate designated standards or has been tested and found suitable for use in a specific purpose.”
Listed products are typically identified by the presence of a product approval mark issued by the testing organization. Product approval marks are the identifying marks or symbols of independent, accredited testing laboratories that indicate that the labeled product meets applicable standards. To qualify for the marks, manufacturers must submit their products to an approved laboratory. The laboratories test products under rigorous, controlled conditions to ensure that the products meet applicable standards. Products that successfully pass all required tests are entitled to bear the testing laboratory’s approval mark.
Confusion regarding approval marks sometime arises from a failure to recognize the distinction between testing laboratories and standards developers. In some instances, the same organizations are involved both in testing and in publishing the standards. When this is the case, an industry standard may bear the name of the publishing company (for example, UL standard 507 for electric fans, or CSA standard C22.2 No 14 for industrial control equipment). This can lead to the mistaken belief that a product must be tested and certified by the organization whose name appears on the standard. In fact, manufacturers are free to use any properly-accredited testing laboratory to test and certify products against the applicable standards, regardless of who published the standards.
Three groups participate in the product testing and certification process: product manufacturers, standards developers, and product testing and certification laboratories.
Product manufacturers are the companies that make the electrical products you inspect. They must be aware of the applicable U.S., Canadian and international standards when designing their products, selecting components used in their products, and when manufacturing these products.
Standards developers are the organizations responsible for creating the standards. Often, they are organized as technical committees that include representatives from government, industry, consumer groups, and end-users affected by the standards. These organizations develop the standards for a particular class of product and work in cooperation with standards publishers. In the U.S., standards developers commonly delegate the responsibility for publishing, maintaining, and distributing standards to organizations like ANSI, ASTM, CSA America, NSF, and UL.
Product testing and certification laboratories are independent agencies hired by product manufacturers. These laboratories test manufacturers’ products and certify that they meet the applicable standards. In some cases (for example, CSA, NSF and UL), affiliated divisions of the same company function as both standards publishers and as the testing laboratory and certification agency. While this has resulted in so-called "CSA standards,” "NSF standards,” and "UL standards,” these standards are available to all accredited testing laboratories for use in testing and certifying products.
When an organization is involved in both standards publishing and product certification, these activities are performed independently and separately. Within CSA Group for example, CSA America is responsible for publishing U.S. standards, while CSA International is a North American product testing and certification agency.
How the Testing and Certification Process Works
A product manufacturer begins by selecting a laboratory. The manufacturer’s choice may be based on a number of relevant criteria, including the lab’s reputation, previous experience with the lab, cost, project deadlines, or other factors.
The manufacturer then provides the testing and certification laboratory with product samples and data such as a list of materials used, schematic diagrams, and component information. After reviewing all of the required documentation, the testing laboratory conducts tests to confirm that the product meets applicable standards for safety and/or performance.
If all the applicable requirements are met, the manufacturer receives written confirmation in a certification report, which includes a summary in the Certificate of Compliance. The product is then considered certified, and the manufacturer can use the certification mark on the product once a licensing agreement is finalized with the testing laboratory. Then the product is listed in the certification agency’s directory listing. Most testing organizations post directory listings on their websites, where any interested party can verify whether or not a particular product has been tested and certified.
What the Marks Mean
Product approval marks are a visible indicator that a product or component meets applicable standards for safety and/or performance. Some of the marks issued by accredited testing labs and commonly found on products certified to applicable U.S. national standards are CSA US Mark, CSA Blue Star, UL, NSF, ETL, and TUV. While some marks may appear on a range of products, others are issued for specific classes of products or products designed for a particular geographic region. Here are some example 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.
The Importance of Accreditation
As previously mentioned, any accredited testing and certification laboratory can test and certify products against a particular standard, regardless of who published it.
A testing and certification laboratory must be accredited to qualify for product testing. Accreditation means that the laboratory has the necessary capabilities, control programs, independence, and reporting and complaint handling procedures. The Occupational Safety and Health Administration (OSHA) accredits product testing and certification laboratories as qualified to test and certify that electrical, gas, and other products meet U.S. standards. OSHA-accredited facilities are known as nationally recognized testing laboratories (NRTLs).
To receive U.S. accreditation, a laboratory must submit application materials to OSHA. OSHA then performs an application review and an assessment review of the laboratory’s organization, programs, and test facilities. The 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. If the application was successful, this second notice signifies that the laboratory is an NRTL. CSA International and Underwriters Laboratories are examples of OSHA NRTLs.
All NRTLs test products against the same sets of standards, regardless of who wrote or published them. So if Laboratory A and Laboratory B are both NRTLs for electrical cabinets and boxes, an electrical box certified by one laboratory has successfully met the same criteria as an electrical box tested by the other.
In addition to OSHA, other bodies accredit laboratories as qualified to test electrical, gas, and other classes of products for the U.S. market. They include the American National Standards Institute (ANSI), the International Council of Building Officials (ICBO), the National Voluntary Laboratory Accreditation Program (NVLAP), the American Society of Safety Engineers (ASSE), and the National Evaluation Services (NES).
The Benefits of Competition
Because multiple laboratories have attained accreditation to test and certify various types of products, product manufacturers have the freedom and flexibility to select a laboratory based on delivery time, cost, convenience, or other considerations such as customer service, for a particular certification project.
A competitive, open testing and certification marketplace helps manufacturers bring their products to market as quickly and economically as possible while also ensuring that they are subjected to the rigorous testing called for by the applicable standards. Together with the listing process, it helps code authorities and inspectors ensure that safety requirements are met within their jurisdictions.
Doug Geralde is the director, Corporate Audits and Investigations, CSA Group, Toronto, ON. In this role, he focuses on liaisons with regulators throughout North America and on a global basis. His group also investigates reported incidents involving CSA-certified equipment and recommends changes to CSA standards committees; conducts audits on internal processes; and initiates, with manufacturers, voluntary recalls and all-points bulletins.
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