Isidor Edward Rittenburg, 81, a retired captain the old U.S. Coast and Geodetic Survey and a veteran of World War II, died of respiratory failure Sept. 11 at Bethesda Naval Hospital. He lived in Bethesda.

He received a certificate of service for his work as an intelligence officer in the Pacific during World War II. During that conflict, officers of the Coast and Geodetic Survey, because of their expert knowledge of geology, were called upon by the Navy to help plan amphibious operations.

Capt. Rittenburg spent 36 years in the Survey before retiring in 1959. In addition to his wartime work, he held field assignments along the Atlantic and Pacific coasts, in Alaska, and in the Philippine Islands, and commanded survey ships. He spent the last seven years of his carrer as the Survey's assistant director for administration.

He was a 1956 recipient of the Commerce Department's Meritorious Service Award.

He was a native of Boston and a 1923 graduate of Tufts University where he earned a degree in civil engineering. After retiring from the Survey, he moved to Utah. He returned to this area following the death of his wife, Mable Ruben Rittenburg in 1966. Capt. Rittenburg was a member of the Institute of Navigation, the American Congress on Surveying and Mapping, the Cosmos Club, and the Bethesda chapter of the Retired Officers Association. He was a past commander of the Montgomery County chapter of the Military Order of the World Wars. He was a Mason, and member of Keystone Royal Arch Chapter No. 32 in Hayttsville, and past president of Bethesda chapter No. 445 of the National Sojourners.

Survivors include a son, John G. Jr., of Roswell, Ga., and four grandchildren.