Some goods must be sold in fixed sizes. These sizes are known as specified quantities. Draught beer and cider are the only products with specified quantities in non-metric units. If you want to order a glass of draught beer or cider, how many sizes up to (and including) one pint can a publican legally serve you? You will probably be surprised to hear the answer.
The answer is four. It is legal to serve one-third of a pint, half a pint, two-thirds of a pint and one pint of draught beer and cider. All quantities of draught beer and cider above one pint must be served in multiples of half a pint (i.e., 1½ pints, 2 pints, 2½ pints, etc.). However, it is rare to find any licensed premises that serves glasses of beer and cider larger than one pint.
I have only ever seen bars, pubs and other licensed premises serving half-pint and one-pint glasses of beer and cider. I have only ever seen a third of a pint of beer and cider served at beer festivals. Apparently, there are no takers for the two-thirds pint option. I wonder why the government ever introduced it.
The Australian system of deregulated glass sizes with markers has been more successful. I wrote about the Australian system in a previous MV article. This article is The pint problem: A new way forward. It is virtually impossible to find any licensed premises in the UK serving thirds of a pint. The Government has allowed quantities of one-third and two-thirds, but they have been rejected by the pub trade.
In Australia, all quantities on glasses are marked in millilitres. Two of them are soft conversions of half a pint and one pint rounded off to the nearest 5 ml. If the UK had followed the Australian model, they might have been more successful.
You can find government regulations of specified quantities at https://www.gov.uk/weights-measures-and-packaging-the-law/specified-quantities.
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You cover how Australia has dealt with beer glass sizes well in the linked article, though I believe the names vary more than you suggest. I have experienced the ‘pint’, the ‘middy’ and the ‘schooner’ in Western Australia. The fact that the smaller glasses have different names (and are not just sub-multiples of a pint) indicates that ‘pint’ is just a name for a glass size, albeit a size rounded up to the nearest 5ml above the imperial pint from which it derived. I suppose Australia went through the same process as the UK when deciding on these sizes and came to the conclusion that keeping a glass size called the ‘pint’ would keep beer drinkers happy. It certainly allows for a ‘large’ glass as the standard which keeps the brewers happy. Like Britain, Australia has a lot of problems with alcohol abuse. That may have something to do with the very large standard glass size. British beers used to be on the weak side years ago but alcoholic strengths have increased over the years as more beers, especially continental ones, have gone on sale. Downsizing the standard glass to, say, a round 250 ml, would be a good step towards addressing that problem. It would also allow for easier comparison between draught beer and the prices of canned beer products. There are too many vested interests for this to happen though, mainly the brewers’ and publicans’ profits.
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Unlike British law, Eire, Australia, New Zealand, and a number of other Commonwealth countries long ago redefined the pint as exactly 570 mL. It is not just a “rounded up pint”, it is a real pint as it is defined as exactly 570 mL. A 568 mL pint would be illegal as it is undersized.
Glassware world-wide for this size is designed and made to hold 570 mL, so despite the undersized definition in the UK, every user of these glasses is getting the full 570 mL. There are more 570 mL pints then there are 568 mL, so we should all consider 570 mL as the “normal” pint and 568 mL as existing only in someone’s fantasy.
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I suggest that the reason why thirds of a pint are not available in pubs is because there is very little demand for them. Pubs are not going to supply glasses of special size just to support the demands of a tiny minority. Two-thirds are more plausible, but the quantity seems complicated, as indeed it is.
In beer festivals, people want to sample and compare many beers. CamRA wants people to drink responsibly, and the smaller third-pint sizes encourage this.
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The International Organisation for Legal Metrology (OIML) has produced a series of 150 different recommendations for various aspects of legal metrology. Examples include recommendation R52 which lays down the physical sizes of cast iron hexagonal weights such as the one shown in the Wikipedia library (https://commons.wikimedia.org/wiki/File:1kg_with_creditcard.JPG).
R138 sets out the requirements for “Vessels for commercial transactions”. (See https://www.oiml.org/en/publications/recommendations/en/files/pdf_r/r138-p-e07.pdf). In simple English, this recommendation covers the requirements for glass and bottles used in commercial transactions – for example, the sizes of glasses used in pubs or the sizes of bottles used in supermarkets. In the case of glasses between 100 ml and 1 litre used for serving drinks, §4.1.1 recommends that national regulations limit size to 100, 150, 200, 250, 300, 400, 500 and 1000 mL.
§4.1.3 provides a case for exceptions given by the text “When justified by local traditions or by special requirements, national regulations may allow additional values for nominal capacities or units (e.g. 0.33 L).”
Much of the recommendation goes on to define how much leeway is allowed in the manufacture of such vessels, both as regards any individual vessels and batches of vessels. It also defines the procedures used to verify that batches are compliant with the regulations. In the case of glasses with a capacity of 200 mL or more, the maximum allowable error is 5 mL + 2.5% of the volume for glasses that have a mark and 5 mL + 5% for glasses that are filled to the brim. Statistical tests are carried out on each batch to ensure that it is unlikely that any one glass the lies outside the limits, otherwise the whole batch must be discarded.
If I wish to import a consignment of beer glasses from a supplier and the government has agreed to incorporate recommendation R138 not law, then I need only specify that they be compliant with OIML regulation 138 and any supplier anywhere in the world can fulfil my order. In practice, EU regulations comply with the OIML specifications so the manufacturers can mark the glass with a CE symbol if it complies with R138. Similarly, if the glass is destined for the UK market, then, assuming that the UK continues to adhere to R138, the manufacture can put a UKCA mark on the glass.
If the UK wants to find a half-way mark between full regulation of the sizes of glasses used in pubs and to total deregulation, then they need only specify that classes shall be compliant with OIML regulation R138. This will allow the sizes listed earlier.
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How does the word ‘pint’ fit in with the definitions given in the reply above by Martin Vliestra? The only way I can think that it does is that the word ‘pint’ is, as I have suggested before, nothing other than a size of glass. The respondent Daniel has suggested on previous occasions that glasses can only be made with increments of 5 ml and that the pint glass is therefore a ‘vessel for commercial transactions’, to use a phrase posted above, of 570 ml. If this is the case, is there any regulation that states this, or do the regulations continue to specify the ‘pint’ size, and sub-multiples of it, without defining what a ‘pint’ actually is?
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The pint is one of the two imperial units of measure that may be used for trade in the United Kingdom. (The other is the troy ounce). The pint is defined in the Weights and Measures Act 1985 (as amended) as being equal to 0.56826125 cubic decimetres. Other imperial units are defined in the Act and may be used as supplementary indicators. The text of the Act can be found at https://www.legislation.gov.uk/ukpga/1985/72.
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“The pint is defined in the Weights and Measures Act 1985 (as amended) as being equal to 0.56826125 cubic decimetres.”
This definition needs to be changed such that one pint equals 0.57 L. Defining a pint to a value containing 8 decimal places is absolutely insane. It is also ignored in the making of glassware for pubs. As far as I know all of the commonwealth countries have long ago defined the pint as 570 mL. Thus England is out of sync with the Commonwealth and the glassware.
What is gained by not synchronising this definition with the real world? If someone actually thinks by resisting in this manner the world is going to give up their 570 mL pint to follow the English, the English are mistaken.
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“The pint is one of the two imperial units of measure that may be used for trade in the United Kingdom. (The other is the troy ounce).”
If the ‘pint’ has been redefined as (more or less) exactly 570 ml, and is not or is no longer 568 ml, which I believe is the closer approximation, is it true to say that it is actually an ‘imperial’ unit any more? Or is the pint *really* just a glass size, the other glass size being half of it? I ask because those who support (or favour returning to) imperial measures hold the ‘pint’ up as proof that the UK is not a metric country. It is true that the ‘pint’ glass is ubiquitous: it’s the standard size. But it would appear from this discussion that it is wrong to call the ‘pint’ an imperial unit used for trade. It is a ‘redefined’, slightly increased version of an imperial unit, but, I submit, it is not an imperial unit any longer.
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Metricnow,
From the Wikipedia article:
https://en.wikipedia.org/wiki/Pint
A pint is defined as one-eighth of a gallon. If you check the history of the pint you will discover that before the 1824 reform of English units there were a number of different gallons, thus a number of different pints. So, with respect to the English redefinition in 1824, is the imperial pint of 568 or 570 mL the “real pint”?
Post 1824, there are two surviving legal “pints”, one being the imperial pint of 568 or 570 mL and the other being the US pint of 231 cubic inches (~473 mL), equivalent to one eighth of the English wine gallon (3.78 L). Was the wine gallon and the beer gallon the same thing in those days or did the beer gallon have yet another definition? Is the American pint the “real pint” that should be used for dispensing alcoholic beverages? Of course, the English would freak out if they were given a glass of 100 mL less for the same price.
The facts are that pints and gallons change from time to time depending on the whims of the then present administration. Thus, there is no true pint and no true gallon. Plus as previously explained, the word pint comes from the Latin word pincta meaning paint and referred to a the painted line on a glass defining a full glass. So any marked glass is a pint glass.
So, a pint of 570 mL is just as true of being a pint as is 568 mL or 473 mL or even 600 mL used in the Australian milk industry. In the US, Whisky and spirits are sold in a 500 mL bottle, also called a pint, sometimes referred to as a metric pint. Beer sold in England also comes in a 500 mL bottle, which is also called a pint. Not to long ago there was chatter about some Champagnes being bottled in pint sizes, but in truth, it is a 500 mL size, called a pint. 500 mL is not a legal pint by definition but is considered a pint in usage. I’m sure most people would not consider any amount between 400 and 600 mL as a pint.
So, everyone needs to get over the hang-up of encountering a 570 mL glass when asking for a pint. 570 mL is now the true replacement for one-eighth gallon despite the English still clinging to the 568 mL definition, a definition that needs to be changed to sync it to real world usage.
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@Daniel It is the Imperial pint that is now defined in UK legislation to 8 decimal places, this being a hangover from the original definition of the pint and gallon. Within the EU it is defined as being 0.5683 litres.
Assuming that both UK and Irish legislation mirrors the OIML recommendations (which I believe the EU legislation does), then a “pint” glass with a brim measurement has a 33 ml tolerance either way and a “pint” glass with a line measurement has a 18 ml tolerance either way. Since the difference between the UK and Irish definitions of the pint are within 2 ml of each other, a manufacturer can produce glasses for both the UK and Irish market using the same production line. Furthermore if he etches the CE and UKCA marks on each, the glasses can be used in either market. I doubt very much that such glasses would be exported to either Australia, the USA or Canada due to the cost of transportation.
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