As scientists at the National Institute of Standards and Technology well know, standards come and go.
Since its start in 1901, NIST (then known as the National Bureau of Standards) has issued thousands of different standards based on the needs and priorities of U.S. industry. Many NIST standards change or are discontinued as industry needs change. One notable exception, Standard Reference Material 5m, is celebrating its 90th anniversary of continuous service to the U.S. steel industry.
Recently renewed for the 16th time, NIST's Cast Iron SRM has changed little since the National Bureau of Standards adopted it from the American Foundrymen's Association in 1906. With sales of 50 to 70 units annually, it remains a popular and reliable standard for steel manufacturers.
Foundries use SRM 5m to verify the accuracy of their chemical analyses. It is necessary to analyze elements in raw materials because the quality and strength of the end product, cast iron or steel, hinge on the concentrations of various elements. In cooperation with the American Society for Testing and Materials, NIST has certified the concentration of 12 elements, including carbon, manganese, phosphorous, silicon and sulfur. Foundries and others can purchase a 150-gram bottle of SRM 5m for $215. If their analysis of the SRM agrees closely with the NIST certified values, they can be confident their analyses of metals with unknown concentrations of elements are accurate.
SRM 5 was one of the first of the more than 125 SRMs that NIST now provides to the steel industry. In 1996 alone, NIST shipped 6,275 SRMs related to the chemical composition of steel alloys. These SRMs are as central to a steel company's operations as a tape measure is to a carpenter.
"We use these things [SRMs] every day," says Thomas Dulski, a senior analytical chemist at Carpenter Technologies Corp., a century-old specialty steel company in Reading, Pa., which supplied steel cables to the Wright Brothers and now specializes in high-end steel alloys for such things as surgical implants and parts for airbag systems. I have worked in the industry for 30 years and I could not imagine operating without [SRMs and] interaction with NIST. It would be a different and lesser industry if it had not been for NIST."
Just as NIST has helped the steel industry improve the quality of its products, it also has lent a hand to numerous other industries through a wide variety of SRMs. One SRM on the forefront of an emerging new technology is NIST's DNA SRM. This standard is helping forensic laboratories validate the results of genetic DNA profiles used in rape, murder and paternity cases. Concern over the accuracy of food labeling has prompted NIST to develop new food-based SRMs that will improve the measurement of nutrient concentrations in food products. Likewise, clinical laboratories long have relied on NIST for SRMs that ensure the accuracy of thousands of medical screening tests.
For more information or a catalog of NIST Standard Reference Materials, contact the Standard Reference Materials Program, Rm. 204, Bldg. 202, NIST, Gaithersburg, Md. 20899-0001, (301) 975-6776, fax: (301) 948-3730, e-mail: srminfo [at] nist.gov.
A non-regulatory agency of the Commerce Department's Technology Administration, NIST promotes U.S. economic growth by working with industry to develop and apply technology, measurements and standards.