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By Alan Earls
Jul 26, 2016
Twenty years ago, in the wake of widespread discoveries of substandard fasteners in construction, defense systems and aircraft, the U.S. Congress took action, passing the Fastener Quality Act, which was signed into law by then-President George H.W. Bush in 1990 as Public Law 101-592. That was one of the most public issues involving quality in recent decades. Then, as now, when discussing quality, the first task is defining it.
It may be that quality is "fitness for use," as asserted by management guru J.M. Juran, or it may be in the eye of the beholder, like the quotation from Supreme Court Justice Potter Stewart, regarding obscenity, that you "know it when you see it." Fortunately, though, there are many ways to define quality in more concrete terms. In fact, its measurement is something that occupies the attention of numerous professionals.
Underlying the concept of quality is the ability to measure with precision. The development of widely used standardized and precise measures in the 19th century, permitting the manufacture of interchangeable parts, became known as the American system of manufacturing and helped propel the industrial revolution in North America. But that critical connection between quality and precise measurement (often in accordance with standards) sometimes is not immediately obvious.
However, when the U.S. Congress did take action on fastener quality, it included the requirement that fasteners used in certain critical applications be tested by an accredited laboratory for conformance to relevant standards. In fact, it is such standards that are the unsung basis by which quality is created, managed and delivered to customers and consumers in just about every field and every industry.
During and since those incidents in the 1980s and 1990s when faulty fasteners made headlines, standards from ASTM Committee F16 on Fasteners have been a big part of the solution. The committee develops standard methods, practices and guides that provide for effective assurance of fastener quality and also help to promote quality assurance methods.
F16 member William King, Porteous Fastener Co., Carson, Calif., says his company relies on fastener standards in everything it does. "Those standards are cited on all our purchasing and testing documents," says King. "Because we are a wholesale distributor rather than a manufacturer, we rely on standards for communicating exactly what we want from our domestic and foreign suppliers," he adds. Working to standards, the suppliers usually seem to get better and better "especially if we keep them regularly informed of changes in specifications," he adds.
"The importance of standards is that they provide product manufacturers clear material, mechanical and dimensional requirements coupled with specific quality assurance and test methods to use to assure they are meeting specific ASTM standards and/or other industry standards," says King. "Standards also provide purchasers with the needed information to verify that products meet such standards." Designers can count on the quality that results from applying standards. For example, organizations such as the Association for Iron and Steel Technology and the American Institute of Steel Construction refer to specific ASTM fastener standards in their own documents, he says. Thus, standards turn out to be a critical element in the safe construction of steel frame buildings as well as in innumerable other applications.
Of course, anything that is ubiquitous can easily become invisible to end users. Thus, when a tire rolls off the factory floor and eventually ends up on your car, hardly anyone along the way stops to recognize the role that the standards developed by ASTM International Committee D24 on Carbon Black play in ensuring its quality.
"Before you can have any type of business arrangements between two parties you have to demonstrate the quality of materials, and before you can agree you must determine what critical properties define that material," says Jeffery A. Melsom, raw material technical leader, Michelin Americas Research Co., Greenville, S.C., and a member of Committee D24.
In fact, commercial transactions, negotiations and contracts conducted without the reference point of standards would be all but impossible without them. Suppliers and their customers need standards to define desired characteristics and quality levels, and later, to determine whether the products provided matched those levels. Once you get those definitions, you must also agree on how you have defined the critical properties and the measurements you need to use. "The challenge is making sure you have and use standardized methods. It could be something developed by the producer or the consumer, and then evolve with wide input and then brought to a standards body, where it can eventually become the standard method or norm," says Melsom.
In the tire industry, for example, manufacturers use many kinds of carbon black. "Carbon black is one of the major raw materials and can affect tire performance like wear, traction and rolling resistance. One must know and understand carbon black and its levels of quality," says Melsom. The goal for companies like Michelin, the world's largest tire manufacturer, is to produce the same tire with as little variation as possible among any of its factories. That's where carbon black standards like those of Committee D24 serve as a reference in helping producers and consumers to precisely define the quality of the carbon black. ASTM even produces a number of Standard Reference Blacks, physical materials that help monitor the precision of carbon black test methods. For instance, there is Industrial Reference Black for determining mix properties, Industrial Tint Reference Black for tint testing, and Sulfur Blacks for calibrating the sulfur content found in carbon black.
According to Melsom, quality assurance rests on four factors: a consensus regarding desired properties, analysis methods to measure those properties, the development of reference materials (in this case, ASTM's Standard Reference Blacks), and finally, a proficiency program to ensure that laboratories, regardless of their location, are capable of performing the analysis and obtaining the SRB defined values.
In the past, the technical aspects of materials were not as well understood as today, says Melsom. The measuring devices and equipment have improved over the years, too. "That is true for every industry, so the standards have evolved," he adds. For instance, in the carbon black area, the industry has discovered that the statistical thickness surface area test (D6556, Test Method for Carbon Black-Total and External Surface Area by Nitrogen Adsorption) is better than the CTAB (cetyltrimethylammonium bromide) test in measuring surface area, and the committee subsequently withdrew that standard.
The process of improvement and evolution is always based on consensus, of course, which tends to produce results with wide appeal, often leading, as has been the case with D24's work, to acceptance internationally as well.
Melsom says whether you are talking about playground equipment or light aircraft, the story is the same: you have to have standards and testing methods that everyone agrees upon. That allows all the players to "go to the same well" on defining characteristics and ensuring the repeatability and reproducibility of a process. "Without that it turns into ‘he-said, she-said' or arguments over whether a particular method is valid. If you don't get that groundwork established, it will not be possible to make a consistent scientific comparison among the material grades," he says. But the impasse that a lack of effective standards would create in business is not the only story. "If you can't agree on the basics, then you won't be willing to pay more for higher quality because you won't be able to distinguish quality differences objectively."
Far afield from carbon is ASTM Committee D13 on Textiles. The committee focuses on standards for raw fibers as well as end-use products like ultraviolet protective clothing, home furnishings, apparel, etc., and qualities such as flammability. Its test methods subcommittee deals with quality assurance from the test methods standpoint. Another subcommittee looks at care labeling for end user products to ensure that consumers understand product care directions and that it defines consistent terminology.
According to D13 member Robert M. Holcombe, a former lab director and now a part-time consultant with ITG Automotive Safety, Greenville, S.C., in the past, the textile committee had built their programs around standards but aimed to give the industry a "full package" from which to work. For instance, he notes, the standards related to clothing cover the mechanical properties of cloth such as the linear density - threads per inch or ounces per square yard - tear resistance, resistance to creasing and folding, pilling resistance and so on. With fire protective clothing, standards quantify heat resistance, fire resistance and thermal transmission.
The rest of the "package" consists of things that make it easier to leverage standards into quality results. For example, notes Holcombe, the committee has technical training programs for certain standards so they can disseminate information on how to use the standards and in turn ensure that companies can document their level of quality. The committee also has proficiency testing programs associated with standards so the companies that are testing a fabric or yarn can be sure that the testing will come out the same no matter which laboratory they use. Holcombe oversees the proficiency test program related to several D13 standards.
Other ASTM International standards that touch most people every day are those dealing with petroleum - they help to ensure that jet engines operate properly at 40,000 ft [12 km] and that cars start easily and reliably when the driver turns the key.
James Bover, ExxonMobil Biomedical Sciences Inc., Annandale, N.J., says that with most petroleum products, having standards is critical. In the case of jet fuel, for instance, "to say that the quality parameters and criteria for the fuel are very important would be trite - they are absolutely essential."
D02 has been producing standard specifications and test methods on petroleum products and lubricants for more than 100 years. Bover says that with respect to test methods, "Generally, we used to focus only on the technical steps that would produce a precise and accurate result. Around 10 to 15 years ago we started to expand this focus to include quality assurance and quality control recommendations to enhance intra- and interlaboratory performance." In 1993, D02 initiated an Interlaboratory Crosscheck Program that provides laboratories with a tool to evaluate their performance relative to other industry labs globally (see sidebar, "ASTM International Proficiency Testing: Getting Labs on the Same Page").
In addition to supporting quality and safety, standards and test methods also level the playing field for users and suppliers, making the conduct of business more efficient. For example, in the automobile industry it is still common for each manufacturer to have its own test methods for certain components or materials, notes Holcombe. Thus, if you are producing items for General Motors, Chrysler and Mitsubishi, "you are probably testing differently for each one, but if you could use a consensus standard, it would be well written by experts in the field, and you could test once for all of your customers," says Holcombe.
In a sense, then, standards have become almost like an industry best practice, says Holcombe. "That's why ASTM standards are growing in importance and acceptance," he adds.
See the November/December 2009 issue for the first article in this series, "Standards Enable Product and Service Compliance."
March / April 2010
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