Dr. Herbert Stelwyn Gates Sr., 82, a physician who had maintained a practice in general medicine in Washington since 1923 and was active in professional organizations, died of a subdural hemotoma Saturday at Carriage Hill nursing home in Bethesda.

He helped organize the general practice section of the Medical Society of the District of Columbia in the late 1940s, and chaired the Society's Traffic Committee for 20 years. He served two terms as alternate delegate to conventions of the American Medical Association, and was president of the George Washington Medical Society from 1949 to 1950.

His other professional memberships included the Southern and Pan American medical societies. He has been affiliated with Sibley Memorial Hospital for many years and helped organize its department of general practice there in 1947.

Dr. Gates received service awards from the U.S. government, for his 25 years with the Selective Service System, the D.C. government, Sibley Memorial Hospital, the American Legion, and the Kiwanis.

He was a Mason. Dr. Gates was a charter member of the Kiwanis Club of Northeast Washington, and was its president in 1957.

He was a member of the Metropolitan Memorial United Methodist Church in Washington.

Dr. Gates was a native and resident of Washington. He was a graduate of Eastern High School and George Washington University's medical school. oHe served his internship at the old Garfield Memorial Hospital and his residency at Sibley.

He served in the Army during World War I.

Survivors include his wife, Pearl W., of Washington; two sons, Dr. Herbert S. Jr., of Virginia Beach, and Wayne R., of Great Falls, Va.; a daughter, Donna G. Chapman of Hartsville, S.C.; a brother, Theodore A., of St. Petersburg, Fla., and nine grandchildren.