Selecting a Material Testing Laboratory

by Walter W. Brown II

Knowing that the laboratory you select has a proven quality program allows
you to focus on turnaround time and other service factors.

It's late in the afternoon, you need to send out a part or material sample for analysis, and you're trying to find a laboratory that will provide accurate testing results while meeting your delivery requirement for the test report. What can you do to ensure you choose a laboratory that gives you the results you need? This isn't a new issue, and you aren't the only one who has dealt with this situation. In fact, this issue has prompted many individuals to become involved in determining the competency of testing laboratories.

Regardless of the service or product your company sells, the issue of the quality of your services or products continues to increase in importance. It's no longer acceptable to simply state that your company provides quality products or services. Today, you must be able to demonstrate by performance documentation that your products or services maintain certain quality levels. Product manufacturers and manufacturing service companies have, for some time, turned to testing laboratories to assist in demonstrating the quality of their products or services. But who determines the quality of the testing laboratories? How can you be assured that you're selecting a laboratory that provides legally defensible, reproducible data? Where should you begin your search?

In addition to occasional source listings published in trade magazines, there are multiple industrial buyers guides that provide lists of laboratories by specific and general testing-laboratory headings. Today, some of these buyers guides can be easily accessed via the Internet, such as the IndustryNet located at In addition to industrial buyers guides, the American Society for Testing Materials publishes the Directory of Testing Laboratories annually. This directory is developed using completed questionnaires submitted by the laboratories.

These sources provide you with the ability to develop a list of laboratories to contact. However, you must be aware that the laboratories listed in these sources aren't guaranteed to deliver accurate testing data. In fact, ASTM states the following in multiple locations throughout its directory:

"ASTM has not attempted to investigate, rate, endorse or place a seal of approval upon any laboratory. Nor does ASTM vouch for the qualifications of the individual laboratories. Therefore, this Directory is not intended, and should not be used, as an ASTM-certified laboratory list of laboratories offering their services for either government or private work."

Once you have a list of laboratories, how can you determine which have established quality programs? Fortunately, for almost 20 years there has been a significant amount of activity that provides individuals with an important screening factor for determining if a laboratory has an established quality program.

In 1977, the International Laboratory Accreditation Conference addressed the preparation of an accrediting standard for laboratories. ILAC presented its drafted standard to the International Organization for Standardization for preparation as an ISO guide. In 1982, ISO/IEC Guide 25 (General Requirements for the Competence of Calibration and Testing Laboratories) was published as a joint effort between ISO and the International Electrotechnical Commission. Today, ISO/IEC Guide 25 has become the worldwide standard for evaluating calibration and testing laboratories.

A 1990 revision of Guide 25 states, "Laboratories meeting the requirements of this guide comply, for calibration and testing activities, with the relevant requirements of the ISO 9000 series of standards." While ISO 9000 addresses the registration of quality systems, ISO/IEC Guide 25 specifically addresses the technical competence of a laboratory in addition to its quality system.

The use of ISO/IEC Guide 25 has increased significantly during the last 10 years. The American Association for Laboratory Accreditation uses the ISO/IEC Guide 25 to perform laboratory audits for 11 testing fields. These fields include acoustics and vibration, biological, calibration, chemical, construction materials, electrical, environmental, geotechnical, mechanical, nondestructive and thermal. As of July, A2LA had 820 accreditations in 41 states, Canada, Germany, India, Italy, Korea, Mexico, Switzerland and Taiwan. To obtain a current list of A2LA-accredited laboratories, contact A2LA at (301) 670-1377 or e-mail

ISO/IEC Guide 25 has become a common document in the accreditation of testing laboratories providing services to the automotive industry. The QS-9000 Quality System Requirements for Chrysler, Ford and General Motors, under Element 4.10.11, states, "Suppliers shall use accredited laboratory facilities ..." According to QS-9000 documentation, an accredited laboratory is defined as "one that has been reviewed and approved by an accreditation body-e.g., American Association for Laboratory Accreditation."

In 1991, some aerospace defense contractors joined together to explore the possibility of establishing an organization that could perform laboratory audits and allow the companies involved to share audit data. This approach eliminates the need for companies to maintain their own internal audit organizations. The result of this approach is the Performance Review Institute, which administers the National Aerospace and Defense Contractor Accreditation Program. For more information on PRI and NADCAP, please call PRI at (412) 772-1616.

A few years ago, only large manufacturers could afford to have an in-house staff conduct auditing outside testing laboratories. Usually, these large manufacturers had significant vendor bases, and their objective was to ensure that their vendors used a laboratory that could provide accurate testing data. With the current pressure in most industries to reduce manufacturing costs, the ability to maintain an internal staff that audits external laboratories has received a significant amount of attention. One outcome has been the establishment of organizations dedicated to auditing laboratories' quality programs.

In addition to looking for specific accreditations, you'll want to know if the laboratory currently participates in any proficiency testing services. A laboratory's ability to provide accurate data has been, and continues to be, assessed by performing what has been referred to as proficiency/round-robin testing. This testing process involves multiple laboratories that perform a standard analysis to determine if laboratories obtain the same testing data. Round-robin testing programs are sometimes conducted by material producers or manufacturers in addition to testing laboratories. If the laboratory is A2LA- or NADCAP-accredited, it's required to participate in proficiency and round-robin testing based on the specific accred-itation(s) of that laboratory.

Using the A2LA and/or NADCAP accreditations as an initial screening process for selecting a laboratory results in a list of laboratories whose quality programs have been reviewed by outside organizations. These laboratories will have demonstrated their ability to provide consistently accurate data. Knowing that the laboratory you select has a proven quality program allows you to focus on turnaround time and other service factors.

You will want to inquire about the turnaround time needed to accomplish your specific testing requirement-which depends on the laboratory's staff, equipment and current workload. You will want to determine if the laboratory has an internal, automated laboratory information system that provides the laboratory staff with the exact status of your analysis and when it is expected to be completed. You should also know how the report will be delivered. Will the report be faxed and/or mailed? Experience shows that when most companies send a sample to a laboratory for testing, they need an immediate response-sometimes that means yesterday.

Fortunately, the development of the ISO/IEC Guide 25, the NADCAP process, auditing organizations such as PRI and A2LA, and proficiency testing have made it possible for you to locate material-testing laboratories that are highly competent. You are now able to select a laboratory while having a high degree of confidence in the accuracy of the testing data.

About the author
Walter W. Brown II is vice president of marketing for Sherry Laboratories. Since 1947, Sherry Laboratories has been providing metallurgical, materials and environmental testing services to multiple industries, including: aerospace, automotive, defense, medical, nuclear, petrochemical, refining and general manufacturing. With laboratories in Indiana, Louisiana and Oklahoma, Sherry Laboratories provides testing services to more than 3,500 U.S. and international clients.

For additional information, contact Sherry Laboratories at (800) 874-3563, fax (317) 747-0228 or visit their Web site at laboratories.