ASTM Cotton Fiber Standards
Support for International Commerce
Cotton has been a major agricultural crop in the United States since the early 1800s and has become a significant fiber in the current world textile market where, between 2000 and 2004, an average of 20.1 million metric tons were produced by cotton-growing countries. (1) From the 19th century, when cotton was grown and consumed within a few countries or geographical areas (2) to the 21st century when it is grown and traded from more than 100 countries, cotton has increased in production and significance in international trade. For the 2004-2005 cotton crop year, China, the United States, India, and Pakistan produced two-thirds of world output from which yarns, fabric, and textile products will be manufactured and traded.
The trail of cotton’s commercial growth began in 1793 with Eli Whitney’s invention of the cotton gin. The gin was designed to mechanically separate cotton fibers, or lint, from cottonseeds. The gin increased the market value of cotton in the 10-year period from 1793 to 1803 from $150,000 to more than $8 million. (2) This proved to be just the beginning of the mechanization of an agricultural crop, from planting and harvesting to processing, spinning and product manufacture.
The first patent for a mechanical cotton picker was filed in 1850. (3) The cotton gin and picker joined the development of mechanical yarn-spinning equipment during the Industrial Revolution in the United Kingdom and the United States during the early 19th century. (4) By the mid-20th century, mechanical harvesting and ginning came into widespread use in the cotton-growing areas of the United States. These technologies were the forerunners of the modern, high-speed harvesting, ginning, yarn processing and spinning technologies used in today’s cotton industry.
The Need for Standards
Because cotton’s growth is dependent upon climate, soil, farming practices, and genetics, the assessment of cotton fiber attributes is elemental to its movement in trade. The commercial trade of cotton bales and fabrics made from cotton yarns among the United States and the United Kingdom, India and Europe, and between the industrialized northern United States and the growth areas in the south, reached such significant volumes that in 1907, the International Cotton Congress asked the United States Department of Agriculture to establish cotton classification standards. (6)
Further, the use of cotton fiber by mills for spinning yarns destined for the manufacture of textiles for household and clothing products, demanded the development of measurements for yarn and fabric attributes.
The first cotton classification standards in the United States were established in 1909 by the Department of Agriculture for fiber color and length grades. The standards for color were, at first, based on physical samples that exhibited a range of color. Cotton fiber length was judged by a human cotton classer using a manual technique that involved pulling fibers away from small bundles into a spread of fibers from which the fiber length, or staple length as it is still known, could be determined.
A Universal Cotton Standards Agreement was established in 1923 between the USDA and 23 other cotton associations from 21 countries. Universal Cotton Standards conferences have met biennially or triennially (with just two exceptions) since 1925. The latest meeting of Universal Cotton Standards was in June 2005 in Memphis, Tenn., at which the signatories again approved the latest universal cotton quality standards for strength, length, uniformity index, micronaire, color grade, and procedures used to achieve agreement. (6)
The USDA became interested in instrument-based classification in the 1930s, with the development and use of colorimeters for reading cotton color. The development of instrumental measurements of other cotton fiber properties, such as length, strength, and micronaire, were developed by USDA. In order to achieve national acceptance of its practices and to provide credence to what was becoming an increasing international need for universal cotton classification standards development, USDA came to ASTM and, in response, Committee D13 on Textiles established Subcommittee D13.11 on Cotton Fibers. ASTM cotton standards for individual measurement of length, strength, and micronaire followed the development of standards for lighting for cotton classing rooms.
High Volume Instrument Systems
During the 1960s and ’70s, the USDA continued its standardization initiative, working with testing equipment manufacturers to combine a full range of cotton fiber quality measurements into an instrumental system. The result was what would ultimately be called high volume instrument, or HVI, systems. Cotton growers in the west Texas region who were concerned about getting true market value for their cotton presented the prime growth area to benefit from standardized cotton classing.
Another justification for developing and using instrument classing was to increase classing volume and decrease the dependence upon human classers. By 1980, USDA’s first full-scale instrument classing operation was started in one of USDA’s classing offices. That year, 10 HVI classing lines were used at the Lamesa, Texas, site. Today, USDA has 290 HVI systems in service6 and there are now an estimated 1,492 HVI systems thoughout the world. (7) In addition to those used by government agencies, HVI systems are also used by merchants, mills, cotton associations, universities and research organizations. USDA estimates that since 1991, when all classing offices were converted to HVI systems, more than 200 million U.S. cotton bales have been classed. (6)
By 1986, two ASTM HVI standards had been developed and approved. The two standards, D 4604, Test Methods for Measurement of Cotton Fibers by High Volume Instruments (HVI) (Motion Control Fiber Information System), and D 4605, Test Method for Measurement of Cotton Fibers by High Volume Instruments (HVI) (Special Instruments Laboratory System), existed separately until they were merged into one non-specific instrument standard D 5867, Standard Test Methods for Measurement of the Physical Properties of Cotton Fiber by High Volume Instruments.
Cotton Standards Around the World
The USDA has taken a leadership role in efforts to bring standardization and acceptance of its HVI cotton classification system into the international arena where cotton is an important product in global textile import and export markets. The International Organization for Standardization (ISO) maintains two standards for cotton fibers: one for the measurement of micronaire (ISO 2403: 1972, Textiles Cotton fibres Determination of micronaire value) and another for equipment and artificial lighting guideline for cotton classing rooms (ISO 4911: 1980 Textiles Cotton fibres Equipment and artificial lighting for cotton classing rooms) but does not have any cotton fiber classification standards. (9)
ASTM with industry support from USDA, Cotton Incorporated, testing equipment manufacturers, and the U.S. Departments of Commerce, Customs, and Homeland Security maintains the basic cotton fiber test method and HVI standards. Additional cotton classification standards are planned for development within ASTM’s Subcommittee D13.11. USDA’s expertise and experience in cotton classification was noted by the International Cotton Advisory Committee’s Expert Panel on Commercial Standardization of Instrument Testing of Cotton when they recommended USDA’s classification system as the model to be used by other countries’ cotton classification process in 2004. (6)
China’s upland cotton production is consumed by that country’s own textile industry. Even though its cotton planting area has increased to the level that it is now the largest producer of cotton in the world, it has become an importer of cotton during the last two years. (10) China’s cotton classification system is currently based on individual instrument measurements and visual color grades. In 2003, the Chinese government made the decision to move toward full cotton classification using HVI systems. The Chinese Fiber Inspection Bureau has been given the task of implementing such a system by 2010. The Chinese agriculture ministry, inspection bureau, and marketing officials have visited USDA’s standards and classing facilities in Memphis for information about HVI classing. During a recent meeting at Cotton Incorporated, the Chinese Fiber Inspection Bureau, USDA, and ASTM Subcommittee D13.11 leaders discussed the relationship between China’s HVI test method standard and ASTM D 5867.
An industry’s needs for establishing technical standards on which business and commerce can be based and then used in the international trade arena is demonstrated in the close relationship between the cotton industry and ASTM International standards development. Today, ASTM Subcommittee D13.11 maintains all cotton standards and works to keep the standards up to date. New and improved cotton fiber standard development is needed in the future to assist global trading, and D13.11 is there to meet the need. //
(1) Cotton Incorporated, Monthly Economic Letter, June 10, 2005.
(2) Joseph’s Introductory Textile Science, Sixth Edition, Ed. P. Hudson, A. Clapp, and D. Kness, Harcout Brace Jovanovich College Publishers, 1993, p 53.
(3) American Cotton Handbook, Ed. D. Hamby, Enterprise Publishers, Third Edition, Vol 1. 1965, p 53.
(4) Yafa, Steven, Big Cotton, S. Penguin Group, 2005, pp 70-146.
(5) Web Museum of Paris, www.ibiblio. org/um/, 11 October 2002.
(6) Knowlton, James. L., USDA-AMS, “Cotton Classing and the Need for a Universal Cotton Quality Evaluation System,” Proceedings, Cotton Council International Cotton Symposium Turkey, “HVI - EFS® Advantage for the COTTON USA Supply Chain”, April 24-26, 2005.
(7) Chewning, Charles H. , Cotton Incorporated, “The U.S. Cotton Management Advantage The EFS® System,” Proceedings, Cotton Council International Cotton Symposium Turkey, “HVI - EFS® Advantage for the COTTON USA Supply Chain,” April 24-26, 2005. 8 Annual Book of ASTM Standards, Vol 07.02.
9 International Standards Organization, Technical Committee 38 Textiles, Subcommittee 23 Fibres and yarns, www.iso.org.
10 United Nations, Committee on Trade and Development, rO.
11 Cotton Incorporated, internal contact reports, April 2005.