Primates leaving Africa 64 000 to 75 000 years ago migrate into the continent 44 000 years before the first British arrive in the late 18th century.

Metric units first become legal for use in Australia in 1947 when Australia signs the Metre Convention (Convention du Metre). John Grey Gorton – born in Melbourne Victoria 9 September 1911 – the illegitimate son of Alice Sinn, daughter of a railway worker and English orange orchardist John Rose Gorton. Educated at Sydney Church of England Grammar School (where he is a classmate of Errol Flynn) and Geelong Grammar School. Attends Brasenose College, Oxford England, where he takes flying lessons and is awarded a British pilot license in 1932. Studies history, politics and economics at Oxford and graduates with an upper second undergraduate degree. During holiday in Spain while still an undergraduate, Gorton meets Bettina Brown of Bangor, Maine, United States. She is a language student at the Sorbonne. Gorton and Bettina Brown marry in Oxford in 1935 and settle in Australia, taking over his father’s orchard, Mystic Park at Lake Kangaroo near Kerang, Victoria. They have three children: Joanna, Michael and Robin. Serves in World War II.

John Gorton becomes Prime Minister of Australia and announces 19 January 1970 that the Government has decided that metrication is best for Australia.

Metrication in Australia effectively begins in 1966 with the successful conversion to decimal currency under the auspices of the Decimal Currency Board. The conversion of measurements – metrication – commences subsequently in 1971 under the direction of the Metric Conversion Board and actively proceeds until the Board is disbanded in 1981. Australia mostly uses the Imperial scheme before 1970 for measurement, which the Australian colonies inherit from the United Kingdom. Australia withdraws Imperial units from general legal use between 1970 and 1988 and replaces them with SI units through legislation and government agencies. SI units are now the sole legal units of measurement in Australia. Australia’s largely successful transition to the SI contrasts with the ongoing opposition to metrication in the United States, Canada, and the United Kingdom.

Although there is debate in Australia’s first Parliament after federation to consider adopting the SI (formerly known as the metric system until 1960) metric units first become legal for use in Australia in 1947 when Australia signs the Metre Convention (Convention du Metre). Imperial weights and measures are most common in Australia until the Commonwealth government begins the metric changeover in the 1970s. SI units are adopted as a worldwide system of measurement in 1960 by international agreement at the General Conference on Weights and Measures.

The metre, kilogram, second, ampere, kelvin, candela and mole are base units and units form from combinations of these base units are known as derived units. SI units are subsequently adopted as the basis for Australia’s measurement standards, whereby they are defined as Australia’s legal units of measurement. In 1968, a Select Committee of the Australian Senate examines metric Weights and Measures and come to the unanimous conclusion that it is both practical and desirable for Australia to change to the SI. Some of their considerations include the inherent advantages of the SI that means that weighing and measuring is facilitated often with substantial increases in efficiency. Educationally, the reform would simplify and unify the teaching of mathematics and science, reduce errors, save teaching time and give a better understanding of basic physical principles. More than 75% of Australia’s exports in 1968 go to metric countries and all countries except the United States are metric or were converting to the SI. They also note that because of Australia’s large migrant programme, more than 10 per cent of people over 16 years of age had used the SI before coming to Australia. They also note that school pupils are widely familiar with the SI because it had been taught in schools for many years. Metrication is already well under way by 1968 in Australian industry. The pharmaceutical industry metricates in 1965 and much of the chemical and electronics industries work in metric units, there being no Imperial units for the latter. One major automobile manufacturer already declares its intention to metricate before the Government announces its decision to change to the SI. The change itself provides a unique opportunity to rationalize and modernize industrial practices and bring Australia’s technical standard specifications into accord with those adopted internationally. The Australian Parliament passes the Australian the Metric Conversion Act on 12 June 1970. This Act creates the Metric Conversion Board to facilitate the conversion of measurements from imperial to the SI.

Here is a timeline of major developments in this conversion process: 1971 – the Australian wool industry converts to the SI. 1972 – all primary schools are teaching the SI alone. Many had been teaching both imperial and metric and later, metric alone since Australia changes to the decimal currency system in 1966. Horse racing converts in August 1972 and air temperatures in September 1972. 1973 – all secondary schools are now using the SI. 1974 – large scale conversion across industries, including packaged grains, dairy products, eggs, building, timber, paper, printing, meteorological services, postal services, communications, road transport, travel, textiles, gas, electricity, surveying, sport, water supply, mining, metallurgy, chemicals, petroleum and automotive services. Most beverages also convert to metric units by the end of 1974. The conversion of road signs takes place in July 1974. A publicity campaign prepares the public. 1976 – the Building and Construction industry completes its change to metric measurements within two years by January 1976. 1977 – all packaged goods are labeled in metric units and the air transport, food, energy, machine tool, electronic, electrical engineering and appliance manufacturing industries convert. 1987 – The Real estate industry converts to metric. 1988 – Metrication completed, with the SI becoming the only system of legal measurement in Australia.

The Metric Conversion Board spends A$5,955,000 during its 11 years of operation, and the federal government distributes A$10,000,000 to the states to support their conversion process. The cost of metrication for the private sector is not determined but the Prices Justification Tribunal reports that metrication is not used to justify price increases. Opposition to metrication is not widespread. The Metric Conversion Board does not proceed with education programmes as polling reveals that most people are learning units and their application independently of each other, rendering efforts to teach the systematic nature of the metric system unnecessary. The Metric Conversion Board dissolves in 1981 even though conversion to the SI becomes complete in 1988. The conversion is the responsibility of the National Standards Commission between 1984 and 1988 (later renamed the National Measurement Institute). Real estate becomes the last major industry to convert in 1987 and the few remaining imperial units are removed from general use in 1988.

An important and very visible sign of metric conversion in Australia is the change in road signs and the accompanying traffic regulations. M-day for this change is 1 July 1974. Australia converts almost every road sign in a month with careful planning. They achieve this by installing covered metric signs alongside Imperial signs before the change and then removing the imperial sign and uncovering the metric sign during the month of conversion. While road signs could not all be changed at the same time, there is little chance of confusion as to what any speed limit sign means during this short change-over period. This is because the previous (MPH) signs had the signage in black on white and were rectangular, in the same style as current US speed limit signs, while the (km/h) signs have the number indicating the speed limit inside a red circle as is done in Europe. Road distance signs are also converted during this period. All new kilometre signs have affixed to them a temporary yellow plate showing the number of miles in order to avoid confusion as to whether the distance is miles or kilometres. These temporary plates are removed after about one year. Dual marking is avoided except for bridge-clearance and flood-depth signs. Though metrication opponents express the fear metric speeds signs would lead to roadway slaughter, this did not happen as most drivers under the age of 25 had been taught metric units at school and through them, their parents were familiar with metric speeds. Thinking that public education would be the most effective way of ensuring public safety, various motoring organizations, regulatory authorities and the media form a Panel for Publicity on Road Travel and plan a campaign to publicize the change. The publicity campaign cost A$200,000 and the Australian Government Department of Transport pays for it. The Board also produces 2,500,000 copies of a pamphlet Motoring Goes Metric. Post offices, police stations and motor registry offices distribute the pamphlet. For about a year before the change, motor car manufacturers fitted dual speedometers to their vehicles and after 1974 all new cars have metric-only speedometers. Several kinds of speedometer conversion kits are available. Road conversion occurs without incident as a result of all these changes.

The building industry is the first major industry grouping in Australia to complete its change to metric. This is achieved within two years by January 1976 for all new buildings other than those for which design had commenced well before metrication began. The resulting savings for builders and their sub-contractors is about 10% a year of gross turnover. Metrication is mostly complete. Road signs are totally metric, as are the speedometers and odometers in motor vehicles and the sale of oil and petrol is by the litre. Australians still commonly talk about vehicle tyre pressure in pounds per square inch. Fruit and vegetables are advertised, sold and weighed by the kilogram, groceries are packed and labeled in metric measures. Schooling is wholly metric. Newspaper reports are mostly in metric terms. In some cases old imperial standards are replaced with rounded metric values, as with horse racing or the size of beer glasses (rounded to the nearest 5 mL). The pre-metric names of beer glass sizes, including the pint, have been retained (although in South Australia the pint of beer is not an imperial pint, as it is elsewhere in Australia).

Dressed timber is often sold in lengths such as 1.8, 2.1, 2.4, 3.0 and 3.6 metres, each multiples of 300 mm, thereby approximating foot length increments, while pipes and conduits may be specified as having diameters of 12, 19, 25 and 32 et cetera mm (based on soft conversions of 1⁄2, 3⁄4, 1 and 1 1⁄4 in). In some cases, goods manufactured to pre-metric standards are available, such as some bolts, nuts, screws and pipe threads and there are some instances where pre-metric measures may still be used: Mass is referred to in kilograms, and baby nappy sizes are specified in kilograms only but some parents give their baby’s birth mass in pounds and ounces. However, this has become less common. Height is measured and given in centimetres. In informal and private contexts a person’s height is still sometimes stated in feet and inches.

Domestic and commercial real estate is advertised in square metres or hectares but though crop yields are described in tonnes per hectare, rural land areas are sometimes still advertised in acres. Weather reports are always in metric terms but some specialized surf reports give wave heights in feet and there are occasional references to the old century, meaning 100 °F, when describing temperatures of 38 °C or more. Imperial measurements are used in preference to metric usually where the product originates from or is intended for an American market (printers, hard-disk drives) or when the size increment for a product is a multiple of an inch (televisions and tyres). A few examples are: Scuba diving uses metric measures but the altitude for sky diving is routinely is given in feet. Aviation, as in many other metric countries, specifies horizontal distances in nautical miles and horizontal speed in knots, but horizontal distance for visibility or clearance from clouds is in kilometres or metres, as are runway dimensions. (The pressure and temperature are also given in SI units, in hectopascals and degrees Celsius respectively). Height or altitude is always specified in feet, as this is vital for safety – as long as one remaining country in the world does not change to metric measurements. (The error in approximating 1000 feet as 300 metres is 4.8 m/16.75 feet. This may be somewhat insignificant at low altitudes. However, the cumulative effect of this error by 30,000 feet (9.15 km) becomes quite significant (144 m/472 feet) The measurement and vertical speed (rate of climb or descent) is given in feet per minute – for much the same reasons height is given in feet. Australia uses metric paper sizes for office use and home printing. (A4 = 210 × 297 mm) However, the term dots per inch (dpi) is still used when printing images. The photo printing industry usually uses imperial sizes for photo dimensions (e.g. 4 × 6 inch rather than 10 × 15 cm). Historical writing and presentations may include pre-metric units to reflect the context of the era represented. Vehicle tyres (as in the rest of the world) mark the rim diameter in inches and the width in millimetres. A car tyre marked ‘165/70R13’ has a width of 165 mm, an aspect ratio (profile) of 70% and a 13-inch rim diameter. Tyre pressures may be given in both kilopascals and pounds per square inch. TV screens and LCD monitors may be described in inches instead of or as well as centimetres, e.g., a Plasma screen may be advertised as 42 inches (106 centimetres), and a computer monitor screen may be advertised in inches. Advertising billboards are measured by feet – because of the still pervading influence of USA practices on such activities. The cultural transmission of British and American English in Australia is a cause for residual use of Imperial units of measure. O how impressive is the magnitude of this task! So much thought, planning and effort go into bringing it about! It is amazing to think about how many members of the general community participate. The change affects all Australians in both their private and professional lives. We recognize this achievement as a great reform effort of our time!

13 Jul 2015