Douglas Oswald Shiels,the son of a lawyer, was born in Hawthorn, Victoria, and received his early education at Hawthorn College (now defunct). He graduated BSc in 1913 and this began a scientific career as student and teacher which lasted for the greater part of his life. Early studies were devoted to chemistry, the major subject for his MSc and DSc Melb and PhD Lond. Later he was granted fellowships of the Royal Chemical Institutes of England and Australia. As a science graduate he lectured in Inorganic and Physical Chemistry in Melbourne and later was concerned with teaching Industrial Hygiene and Occupational Health. In 1934 he was appointed for three years as chairman of the Medical Board at Mt Isa, Qld., where lead poisoning was a major problem. After a short period as RMO at Broken Hill and District Hospital NSW he joined the Department of Health, Victoria in 1937, from which he retired as chief industrial hygiene officer in 1956. He established a laboratory and with trained staff the Industrial Hygiene Division was concerned with Industrial Hygiene and Occupational Health problems.

His knowledge of chemistry and medicine made him a valuable member of committees. He was a member of the Poisons Advisory Committee of the Pharmacy Board of Victoria for more than five years and between 1944 and 1961 he was active on committees of the National Health and Medical Research Councils on Industrial Hygiene and Occupational Health. He was forthright in expressing his views which were always well respected by his colleagues. He was always interested in research. After WW1 he spent three years on chemical warfare at London University and later in the Department of Health, Victoria. He was interested in chemistry and medicine and contributed papers on these subjects to appropriate scientific journals.

Douglas Shiels was intensely loyal and had military service in the two World Wars. From 1915 to 1919 he held a commission in the 59th Battalion Australian Infantry Brigade and was gas officer to the 15th AIF. In France he was twice wounded. In the Second World War he was chemical advisor at Army Headquarters for a considerably period. Douglas Shiels was a genuine and humble person of strong moral principles. He led a temperate life and did not indulge in strong language. To refer to someone as a "big oaf" was strong disapproval indeed. He was a regular attendant at Church and remained a staunch Presbyterian and active in church affairs all his life. He held strong views on political questions of the day and enjoyed discussions on these subjects with those of completely opposite political convictions. While employed in the Department of Health he was prone to supplement the meagre supply of coal for the fires (the only form of heating in those days) with "paper bricks" made with very tightly rolled sections of newspaper.

He remained active after his retirement in 1957. He enjoyed reading not only scientific journals but also fiction, particularly mysteries. He was a consultant to CSIRO on occupational safety and visited divisions of the organisation throughout Australia. He also held a position as medical officer for five years with the then Melbourne and Metropolitan Tramways Board. There was one daughter of his marriage in late middle life to a member of the nursing profession. Douglas Oswald Shiels enjoyed a full scientific life, was an authority on Industrial Hygiene and Occupational Health and had academic qualifications of which he was deservedly proud. It was a privilege to have known him during his working life in the Victorian Department of Health.