<P> The British Virgin Islands also requires that beer and cider be sold in pints . Also, in Canada, water amounts in air purifiers are advertised in pints as well as BTUs ("British thermal units"), see metrication . </P> <P> In Australia and New Zealand, a subtle change was made to 1 pint milk bottles during the conversion from imperial to metric in the 1970s . The height and diameter of the milk bottle remained unchanged, so that existing equipment for handling and storing the bottles was unaffected, but the shape was adjusted to increase the capacity from 568 ml to 600 ml--a conveniently rounded metric measure . Such milk bottles are no longer officially referred to as pints . However, the "pint glass" in pubs in Australia remains closer to the standard imperial pint, at 570 ml . It holds about 500 ml of beer and about 70 ml of froth, except in South Australia, where a pint is served in a 425 ml glass and a 570 ml glass is called an "imperial pint". In New Zealand, there is no longer any legal requirement for beer to be served in standard measures: in pubs, the largest size of glass, which is referred to as a pint, varies, but usually contains 425 ml . </P> <P> In Canada, the "pint of beer" served in pubs and bars has long been considered a colloquial term for "a large glass of beer". Legally speaking, after 1873, it was defined as one British imperial pint of 20 imperial ounces . On the other hand, the United States continued to use a smaller 16 ounce pint, while in French Canada after 1873 a "pinte de bière" was defined as a much larger 40 ounce quart of beer, so confusion arose to which was being used . Prior to 1961, bottled beer in Canada was served in two sizes, colloquially known as "quarts" and "pints". They were 22 and 12 imperial ounces (625 and 341 ml), respectively, which were much smaller than the British units . Some provinces banned the sale of beer in the larger bottle . For example, in Ontario in the 1950s only the smaller size could be sold, but in Quebec both sizes were about equally common . The numerous incompatibilities between traditional Canadian, British, French, and American unit systems was one of the driving forces behind metrication in Canada . </P> <P> Draft beer in Canada, when advertised as a "pint", is legally required to be 568 ml (20 fluid ounces). With the allowed margin of error of 0.5 fluid ounces, a "pint" that is less than 554 ml of beer is an offence, though--to the detriment of consumers--this regulation is often violated and rarely enforced . </P>

How many ounces in a pint of beer in canada
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