David B. Spangenberg, a mechanical engineer who worked for the federal government for more than three decades, died Feb. 7 at his home in Silver Spring, Md. He was 79.

The cause was acute appendicitis and sepsis, said his wife, Jane W. Spangenberg.

Mr. Spangenberg began his career in the 1950s at what was then the National Bureau of Standards — now the National Institute of Standards and Technology — in the engineering metrology department. He worked there for 18 years before moving to the Washington Navy Yard, where he was chief of the Navy Eastern Standards Laboratory for 18 years until his retirement in 1987, his wife said.

His professional organizations included the American Society of Mechanical Engineers.

David Byron Spangenberg was born in Takoma Park, Md. He was a 1952 graduate of Montgomery Blair High School in Silver Spring and received a bachelor’s degree in mechanical engineering from the University of Maryland in 1956.

Mr. Spangenberg was a longtime board member at Daleview Pool in Silver Spring and officiated at his children’s swim meets through the Montgomery County Swim League. He volunteered with the Boy Scouts and the Girl Scouts and was a member of Silver Spring Presbyterian Church for more than five decades.

Mr. Spangenberg also taught pottery classes through the Montgomery County Public Schools adult education program from 1987 until he suffered a stroke in 2002.

Survivors include his wife of 58 years, Jane Wildermuth Spangenberg of Silver Spring; four children, Susan Writtenberry of Suffolk, Va., Nancy Leab of Waynesboro, Pa., Scott Spangenberg of Silver Spring and Thomas Spangenberg of Forest, Va.; three brothers, James Spangenberg of Rockville, Md., Ronald Spangenberg of Norfolk and Roger Spangenberg of Prospect, Va.; 13 grandchildren; and nine great-grandchildren.

— Emily Langer