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Kathryn Hach-Darrow (1922–2020)

Kathryn (Kitty) Hach-Darrow, was a true pioneer in entrepreneurship and a dear friend to the American Chemical Society. Although Kitty was not herself a chemist, her contribution to the world of chemistry was immenise. Hach-Darrow and her late husband, Clifford, founded the Hach Chemical Company in 1947 as a small water analysis company, which they grew into a multi-million-dollar chemical corporation. Hach-Darrow contribution to, who was an avid pilot. The Hach family started the Hach Scientific Foundation in 1982 to promote chemistry education through scholarships.  In 1999, Hach-Darrow sold the Hach Chemical Company to science and technology company Danaher.

While Clifford oversaw the company’s research and development, Kitty handled business operations, marketing, and other general management. By introducing chemistry to the field of water analysis the Hach Chemical Company could guarantee safe, clean drinking water in town after town throughout the United States. 

An avid flyer, she logged thousands of flight hours while promoting the analysis kits, distributing them to remote towns, and providing technical training and on-site problem solving. Over the next half century Kitty and Clifford guided the company’s growth into a global leader in water purification.

The company was instrumental in standardizing water-purification tests and pioneered titration test kits and many world-standard water-testing instruments. The company’s tests were designed to be simple and effective, using visual comparisons against color standards and nontechnical directions.

Hach-Darrow was the first woman director of the American Water Works Association. In 1982 she and Clifford established the Hach Scientific Foundation to support science education by sponsoring student tuition and teacher education.

In 2003 she was honored with the Pittcon Heritage Award, jointly sponsored by the Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy (Pittcon) and the Chemical Heritage Foundation, now the Science History Institute, in recognition of her roles as cofounder and CEO of Hach Company and architect of its business model and culture; of her involvement with customers in ensuring safe, clean water throughout the land; and of her commitment to education, leadership, and science. 

Kathryn C. Hach-Darrow, and family endowed millions of dollars to the American Chemical Society in support of its educational programs. Hach-Darrow died in Loveland, Colorado, on June 4, 2020 at the age of 97.

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  2. Kitty Hach-Darrow, C&EN obituary. Retrieved from
Katherine Hach Darrow
Photo courtesy Linda Wang, C&EN