ASTM International’s Proficiency Testing Programs are designed to provide participating laboratories with a statistical quality control tool that enables them to assess their performance compared to other participating labs. It is a quality assurance testing program where identical samples are sent to participating labs and analyzed using standard test methods and results reported for statistical treatment. This article provides a general overview of the ASTM programs and benefits provided to participants and to sponsoring ASTM technical committees.
Using the services of outside contractors, ASTM International coordinates the preparation and distribution of test samples. Each participating laboratory is provided with a set of test instructions, list of methods to be used, and a customized data report form for recording and submitting results to ASTM. All data received at ASTM is handled in a confidential manner.
ASTM prepares a statistical summary report that includes an overall statistical summary table of all data received with randomized lab ID codes to maintain lab confidentiality. Final summary reports include:
• Data summary tables showing the results for all laboratories for each test parameter;
• Statistical results;
• Charts and graphs showing distribution of results;
• Table of contents bookmarked by method for easy and convenient use in locating data tables.
The focus of the programs has been and continues to be on the use of the ASTM International methods that are commonly used by laboratories. Some ASTM programs have incorporated the use of other methods (International Organization for Standardization, European Norms, and Underwriters Laboratories) and draft ASTM methods. Methods cited and used in the program are determined through input of the sponsoring technical committee and program participants.
ASTM staff provides the program management and administrative support that includes program registration and marketing, selecting and coordinating contractors for sample preparation and distribution, obtaining test materials, accounting and legal review, and processing and distributing statistical summary reports. ASTM coordinates the preparation and distribution of test samples, working with and utilizing the services of providers of bulk sample materials and contractors who prepare, package, and distribute homogeneous samples.
Example of a graphical report page from the motor gasoline program
Sponsoring technical committees provide the technical direction, which includes the selection of program tests, types of samples, specific reporting requirements, test instructions and contractor requirements to prepare, package, test for homogeneity and distribute samples.
Within the past two years ASTM has begun a separate business initiative, the Interlaboratory Study Program, to provide administrative and statistical support to assist technical committees in generating data that support the precision and bias statements of ASTM methods. While there are similarities in this program to that of Proficiency Testing Programs, the intents of the two programs are not the same. The focus of the ILS study is to validate the repeatability and reproducibility of ASTM methods using multiple samples and a smaller number of labs. The focus of PTP is to provide a tool that enables a lab to periodically assess its performance in running methods in an ongoing program scheduled throughout the year. PTP participation is open to any laboratory.
The ASTM International PTPs have experienced steady growth since the start with five programs in 1993. As of the end of 2006, there were 35 programs. There are over 3,000 units of laboratory participation, and over 40 percent of these laboratories are non-continental U.S. laboratories, reflecting the significant international use and acceptance of ASTM methods.
Units of participation reflects laboratory participation in multiple programs.
Other ongoing programs conducted through the support of ASTM technical committees include Committee D02’s National Exchange Group (for engine testing) and the Cement and Concrete Reference Laboratory of Committees C01 on Cement and C09 on Concrete and Concrete Aggregates. CCRL is an ASTM International program operated through NIST that includes proficiency testing in construction material areas for cements and concrete.
The Proficiency Test Program provides many benefits to laboratories and to ASTM technical committees.
• Provides laboratories with a statistical quality assurance control tool to compare their performance for conducting methods with other laboratories worldwide.
• Provides laboratories with an objective means of assessing and demonstrating the reliability of the data they produce for their internal and external customers.
• Provides a program to satisfy participation in a proficiency testing program as part of laboratory accreditation requirements.
• Provides useful internal quality control samples for use in control charts or for troubleshooting problems with test methods through residual test materials as well as published statistical data.
• Provides a potential training tool for laboratories to monitor the performance of laboratory technicians (alternating technicians in different test cycles or in the use of residual test material).
• Provides companies that have multiple laboratories from numerous locations the ability to conduct a comparison of their corporate-wide data with laboratories in the global market place.
• Offers data for comparing results and statistics among several test methods that measure the same quality parameters.
• Offers laboratories a tool for identifying and managing laboratory bias over time.
ASTM International technical committees benefit by being recognized as the global technical sponsors and leaders of the programs for their related industries. ASTM provides committees with copies of data reports and other information received, coded to maintain lab confidentiality. Committees receive data and other related information collected from laboratories on their methods that, over the years, have led to the clarification and revision of several standards. Proficiency test data provides opportunities to validate test method performance under real-world conditions.
ASTM International’s dedicated technical committee members provide their expertise to the program structure, statistical treatment of data and formats of final reports. Participants in the program are encouraged to provide input and recommendations on program design that will provide the greatest benefits to them. ASTM stays focused on responding to industry trends and needs, from program design to the content and distribution of final summary reports. A major ASTM objective over the past few years has been to streamline both the data entry process and the distribution of final reports in a more timely fashion.
ASTM’s global Proficiency Testing Programs handle various sample preparation and distribution needs.
ASTM has implemented electronic data capture and final report distribution for all programs. PTP data report forms, customized for each program, are electronically provided for each test cycle, which allows labs to enter their own data directly in the database maintained at ASTM. Where appropriate, the data entry fields for methods on the form are limited to specific reporting rules in order to provide uniformity in data submission by all labs. Participants receive e-mail notifications announcing the electronic availability of test instructions and data report forms and final statistical summary reports that are searchable in PDF format.
Electronic enhancements have resulted in a dramatic decrease in the turnaround time for the delivery of final reports to program participants. Reports are distributed within 30 days upon completion of the program reporting deadline. This enables participants to take necessary corrective actions sooner that affect their quality assurance practices. This has a positive impact on their overall testing and the products or services they offer in the marketplace or within their companies.
All draft final reports are initially screened and reviewed by ASTM International staff. Draft reports are also reviewed by technical contacts in the committee. This process adds technical value and credibility to the reports before being released to participating laboratories.
The breadth of the ASTM Proficiency Testing Program is as diverse as the industries represented in the 35 programs. Many types of testing are conducted across all programs. Program areas include textiles, metals, plastics, engine coolants, insulating fluids, aromatic hydrocarbons and petroleum and lubricant products.
The textile PTP entails the mechanical analyses of three different weight fabrics twice a year. The five metals programs cover the chemical analyses and mechanical testing of various grades of carbon and stainless steel, aluminum, gold and ores assayed from mine waste. The four plastics programs, depending on the resin sample molded, involve a series of ASTM International/ISO mechanical properties tests in addition to program scopes that focus exclusively on flammability ratings and routine physical and optical tests. The program for new and in-service (used) transformer oil offers the insulating fluid industry two overall product integrity testing programs that are conducted biannually. The engine coolant and aromatic hydrocarbon programs challenge the participants twice yearly in their ability to run routine product quality verification tests.
Across the 21 Interlaboratory Crosscheck Programs established for the petroleum industry, a variety of lubricants and petroleum fuels and refinery products are analyzed in programs performed by laboratories globally two to three times yearly up to monthly for two fuels, namely, reformulated gasoline and ultra-low sulfur diesel fuel. Routine ASTM chemical, physical and optical tests typically used by refinery product development labs, as well as those commercially testing used oil products, participate across seven fuels and 13 lubricant Interlaboratory Crosscheck Programs. New product development labs are challenged to produce “reproducible” results daily with minimal bias. Third-party contract labs who serve the petroleum industry participate widely and in large numbers across all programs at the request of those refineries that utilize their testing services and monitor the quality of their testing.
ASTM International welcomes ideas for new programs. Requests for new programs should be directed to ASTM PTP staff. Staff will work with the relevant ASTM technical committee and industry to evaluate program need, scope, design and required services necessary to provide a quality program. Participation in the program is open to any lab. For more complete information on the scope and design of each ASTM Proficiency Testing Program and Interlaboratory Crosscheck Program, please visit the ASTM Web site. //