Arthur Frederick Alan Harper was born on 5 July 1913.  He was educated at the University of Sydney where he attained his Master of Science.  He was awarded the University Medal for Physics on graduation.

In 1940 Alan Harper was appointed to the staff of the Commonwealth Scientific and Industrial Research Organisation's National Standards Laboratory and over a period of 40 years became a senior principal research officer responsible for work in the fields of heat and temperature measurement and low temperature physics.  He played a leading role in the establishment of the National Standards Commission and c1959 was appointed Assistant Secretary, and from 1964 to 1981 Secretary to the Commission.  During this time Mr Harper performed a major role in drafting the Weights and Measures (National Standards) Act, in particular those provisions relating to verifying authorities and traceability.  The Minister announced his appointment as Chairman to the Commission in September 1978 and he held that office until December 1981.

Mr Harper gave the initial briefing to the Senate Select Committee on the Metric System of Measurement, and was its Technical Consultant throughout its sittings 1967-68.  During this time Mr Harper was instrumental in shaping the course of metric conversion in Australia. Between 1965-70 he acted as Australian Representative on the International Organisation for Legal Metrology and was appointed Executive Member of the Metric Conversion Board in 1970.  He was also a member of the Papua New Guinea Metric Conversion Commission between 1972-75 which guided that country into metrication.

Mr Harper was consulted by the governments of New Zealand, Canada and Britain on the changeover from the imperial to the metric system.  He also addressed the United States Congress on the subject.  Upon the finalisation of metrication in Australia, Alan Harper's contribution was recognised in 1976 when he was made an Officer of the Civil Division of the Order of Australia.

Alan Harper held the presidencies of the Royal Society of New South Wales (1959), and the Australian Institute of Physics (1970-71), of which he was the Foundation Secretary.

Alan Harper died on 10 September 1991 in Sydney at the age of 78.