Clifford C. Hach and Kathryn Hach-Darrow

Clifford and Kathryn Hach

Clifford and Kathryn Hach. Courtesy Kathryn Hach-Darrow.

In the 1940s the husband-and-wife team of Clifford C. Hach (1919–1990) and Kathryn “Kitty” Hach (b. 1922) launched the Hach Chemical Company, which became a leading producer of water-testing reagents and instruments. Hach Chemical ensured that clean water flows from household taps and everywhere that water quality is an issue.

Clifford grew up during the Great Depression. Before the crash of 1929, his father had owned and operated a hardware store in a small town in Iowa, a store that a technologically inclined boy could enjoy to the fullest. Economic bad times forced the family with its five children to move out to a farm where they could live off the land. In 1938, at considerable economic sacrifice to his family, Hach enrolled at Iowa State University. There he began studying electrical engineering, in line with some of his boyhood projects in radio communication, but the subject of chemistry stole his heart. He did not receive his bachelor’s degree until 1947 because World War II intervened and talented undergraduates were co-opted by their Iowa State professors to work on various wartime projects at the university. Some of these projects related to the Manhattan Project to make the first atomic bombs. Another was the production of a better carbon dioxide fire extinguisher for the navy to use aboard ships.

The Depression also affected Kitty’s experiences growing up in Missouri. Her father, originally a prosperous car dealer with an enthusiasm for aviation, was forced by circumstances to sell his plane and move his family to a farm. Kitty earned money for her college tuition by raising turkeys for market. She studied at Christian College (now Columbia College) before transferring to Iowa State University to prepare to become a home economics teacher. At Iowa State she particularly admired Nellie Naylor, a chemist in the home economics department who inspired generations of women to enter chemical professions. At the university she met Clifford, and they married at the end of her junior year in 1943. Four years later they established their company with just $15,000 that Clifford had earned from the sale of his patent describing a new way to generate carbon dioxide to fight fires.

While Clifford oversaw the company’s research and development, Kitty dealt with business operations, marketing, and other general management. Over the next half century they guided the company’s growth into a global leader in water purification. Meanwhile, they raised three children, who were allowed the run of the ever-enlarging Hach plants.

Hach Chemical was instrumental in standardizing water-purification tests and pioneered many world-standard instruments for testing water. Their tests were designed to be simple and effective, with nontechnical directions. After Clifford’s death in 1990, Kitty led the company while their son Bruce gradually took on more responsibility. In 1995 she married Donald Darrow, a retired airline pilot. In 1999 the Hach Chemical Company became a subsidiary of the Danniher Corporation. The Hach family, through the Hach Scientific Foundation founded in 1980, has been extraordinarily generous over the years in supporting chemical education at all levels and in many forms.

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The Center for Oral History captures and preserves the stories of notable figures in chemistry and related fields, with over 425 oral histories that deal with various aspects of science, of scientists, and of scientific practices. For more information please visit CHF’s Oral History Program or e-mail oralhistory@

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CHF’s Beckman Center for the History of Chemistry was started with a generous grant from the Arnold and Mabel Beckman Foundation in 1987.


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