Types of Conformity Assessment
(3rd party only)
Certification is the process by which a third party provides written assurance that a product, service, process, or person conforms to a set of requirements (hereafter, the term "product" is used to refer to a product, service, process, or person.). The third party generally provides such assurance in the form of a written attestation, such as a certificate or an authorization to use the third party's certification mark on approved products. Most certification programs also publish a list of certified products for use by purchasers, users and regulators.
Many certification programs focus on product characteristics related to health, safety and protection of the environment. In addition, certification programs also focus on other product performance characteristics.
Certification systems are also used to enhance the purchaser's ability to compare product attributes, such as the usable volume of a refrigerator or grades of motor oil. In these cases the certification provides confidence that the rated volume or viscosity is based on testing and measurement in accordance with accepted standards. Still other programs certify that products actually come from a certain place, such as potatoes grown in Idaho. These types of certification programs are often developed by suppliers, or trade or professional organizations in response to a market need for reliable information on product characteristics.
ISO/IEC Guide 65, General requirements for bodies operating product certification systems, (to be replaced by ISO/IEC 17065) contains a set of general criteria for the operation of a certification program by a third party. This standard is used by many but not all certification programs.
A competently operated certification program can provide a valuable communication tool that can reduce the cost of exchanging information among sellers, buyers, and other interested parties. However, the quality of the information conveyed via a specific certification program depends on many factors. Users of certification results need to be educated on the details of the certification process to enable them to assess the value of certification information and to make intelligent choices regarding its usage.
Product certification programs can be voluntary or mandatory and they may be carried out by either private sector bodies or government agencies.
Certification has two essential characteristics. It is conducted by an independent third party and includes some form of surveillance activity. Surveillance is a group of activities conducted by a certifier to ensure ongoing compliance once initial compliance has been determined. Post-market surveillance involves the evaluation of certified products taken from the marketplace to determine if product requirements continue to be met. Pre-market surveillance is the checking of products before they reach the market and may include audits of the supplier's process control systems and/or inspection of the production. In other certification systems, surveillance is accomplished by requiring all or some significant part of the activities used initially to determine compliance to be re-conducted on a periodic basis. This recertification process can take the form of retesting or re-assessing the characteristics of interest at prescribed intervals. Certification is very useful in situations that involve mass-produced products and characteristics that cannot be readily inspected.
Many private organizations, as well as federal and state agencies in the United States, certify products ranging from electrical cords to meat products. In addition, many certification programs are operated at local government (city, township, county, etc.) levels. Consumers see evidence of the extensiveness of certification-related activities when they see, for example, the Underwriters Laboratories (UL) mark on such diverse products as electric coffee pots and fire extinguishers or when they see the NSF mark on products ranging from plumbing equipment to food and beverage vending machines. The U.S. Department of Agriculture's (USDA) certification mark can be found on poultry and other agricultural products, while the U.S. Department of Energy's (DOE) Energy Star mark can be found on many electrical and electronic products that have achieved a certain level of energy efficiency. These are only a few of the many certification marks which may appear on consumer products.
Confidence in Product Certification
Third-party certification programs can differ greatly from one another. The degree of confidence that can be placed in a particular certification program depends on many factors, such as the adequacy of the product standards used; the program's comprehensiveness (the number and types of testing and inspection methods used within the program to assess conformity); the size of the sample and the type(s) of sampling process(es) used; the use of quality management system requirements; the competence of the personnel involved in the program; the adequacy of the facilities and equipment; and the nature and extent of any surveillance or follow-up procedures used to assure that product continues to conform.
Certification programs can vary in the types of procedures used. Certification programs for the same product may use diverse sampling techniques and test methods and have different product requirements. Therefore, two certification programs that conform to requirements of ISO/IEC Guide 65 and which certify the same product may not provide the same level of assurance of conformance In fact, the two programs may be certifying very different characteristics of the same product.
For example, one product standard may cover the heating element in an iron, while another may contain requirements for the safety of the cord attached to the iron. Two certification programs, each using a different standard - one for the heating element and one for the cord, may claim to be certifying the safety of the iron. In fact, the two programs would be certifying very different safety characteristics of the same product. In addition, one program may test each and every iron, while another might test only a pre-production sample or a prototype. One program may periodically pull samples from the marketplace and test them for continued conformance, while another may have the supplier send in samples for verification of continued conformance. Although both programs could conform to the requirements in ISO/IEC Guide 65, they would be far from equivalent. This is one of the difficulties that trade and regulatory officials, buyers, and other interested parties encounter in accepting certification results from different certification programs.
Generally speaking and assuming that the product standards used in the program are adequate, the comprehensiveness of the program is another factor that must weighed in determining the degree of confidence that can be placed in the results of a certification. The more techniques used and the larger the sample size, the more assurance that can be placed in the product's conformance. However, more comprehensive programs also tend to be more costly. Cost needs to be weighed against the risks associated with the product's nonconformance.
In addition, because standards, testing, and certification are closely linked; strengths as well as deficiencies in any one area can have significant consequences for the other areas. For example, improvements in the test methods used in a certification program can significantly increase the capability of a laboratory to produce better test data, which may then be used in and improve the quality of a certification program.
However, if the certification program is supposed to be certifying the safety of a product, and the product standard does not adequately address all important safety characteristics of the product, then the value of the certification program may be questionable. However, a properly conducted certification program can benefit the free flow of goods into the marketplace. Certification programs can provide buyers, government agencies, and other interested parties with a means of assuring that a product meets the requirements contained in a standard, regulation, or other document. Certification programs can verify that a particular product meets a given level of quality or safety, providing the user with explicit or implicit information about the characteristics and/or performance of that product. Certification can also increase a buyer's confidence in a product and furnish useful product information.
Potential problem areas include:
1. Use of Certification as a Substitute for Improving Quality of the Product and the Manufacturing Process
As Deming has pointed out, quality must be designed into the product and assured through an effective and efficient manufacturing process. Certification and other types of conformity assessment processes can provide information on whether the desired end result has been achieved. Since certification usually this occurs late in the manufacturing process, it does not improve the quality of the products.
2. Use of Inappropriate Product Standards
Standards, which cover all essential characteristics of the product necessary to ensure a given level of quality or safety, may not be available or may not be selected for use in a certification program. The introduction of new technology and new products may also be inhibited if there is no provision for handling products which fall outside the scope of the standard. Standards may also contain specifications that are unnecessary and not based on well documented research or information.
3. Lack of Adequate Test Methods
Test methods may not adequately measure all essential product characteristics included in the certification program in a cost-effective manner. In addition, sampling requirements may not be sufficient to ensure that the certified products adequately represent the entire production line.
4. Lack of Technical and Financial Competency on the Part of the Certifier
The certifier may lack the necessary technical competence and resources to properly use and maintain the test equipment and to conduct the certification process. The organization may not have developed adequate written documentation on the certification requirements and procedures or may not have kept adequate records on the results. In addition, the certifier might also have biases which compromise the integrity of the results.
5. Public Misperception Regarding Legal Responsibility for a Certified Product
Legal responsibility for the quality and/or safety of the product generally rests with the manufacturer, despite frequent public misperception that the third party certifier is responsible.
6. Lack of an Adequate Appeals System
Disagreements may occasionally arise among parties participating in a certification program. Some programs do not have an adequate and impartial appeals mechanism to handle disagreements that cannot otherwise be resolved.
7. Lack of Knowledge on the Part of Users of the Certification Scheme
Buyers who rely on a certification and who are not adequately informed as to the purpose, scope, and technical limitations of the resulting certification may be misled as to the meaning and degree of confidence that can be placed in the certification mark or certificate of conformity.
8. Lack of Adequate Surveillance and Enforcement
Without an adequate process to ensure that any misuse of the certification mark or certificate of conformity is dealt with efficiently and effectively, the mark's integrity may be compromised. Certification programs should take steps to ensure that certified products that are subsequently found not to conform are either recalled from the marketplace or have their marks or certificates of conformity removed.
9. Incompatibilities among National Certification Schemes
As noted above, national certification schemes for the same product or group of products can differ significantly in the standards used and product characteristics that are assessed, the sampling process and the test methods used, and other program aspects. Such differences have the potential to create barriers to trade.
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