There is an ISO standard for making a cup of tea.

ISO wrote the standard for the shipping container (it also wrote one for making a pot of tea)

In October 1946, 65 delegates from 25 countries met in London to work out how the world was going to agree on things now the war was over. What came out of it was the International Organization for Standardization, which started operating in February 1947.

They hit a problem straight away. In English the acronym would be IOS, In French it'd be OIN, So they went with ISO instead, From the Greek isos, meaning equal, so it'd come out the same in every language. First thing the standards body ever standardised was its own name, which is a bit much when you think about it.

It's published over 25,000 standards since, across more than 800 technical committees. The whole thing is boring on purpose. The very first committee they set up, TC 1, was screw threads. ISO 668 is why a steel box loaded in Shenzhen fits the ship at one end and the lorry at the other, which is more or less why globalisation happened. ISO 8601 is why the date on your bank statement isn't ambiguous. ISO 216 is why A4 is A4. ISO 3166 is why your country gets two letters.

And then, filed in among all that is ISO 3103, which is how to make a cup of tea.

I fully thought someone had made this up. They hadn't.. and I started reading into the lore of brew making and lost about three hours to it.

It didn't reach us from Geneva, we sent it there. It started in 1980 as BS 6008 at the British Standards Institution, it went to ISO and came back down as the international one for everyone else to observe. It sits under Technical Committee 34, which is apparently food products and beneath that under Sub-Committee 8, which is tea. So there's a tea sub-committee and it has meeting, Somebody has it in their calendar. Britain holds the secretariat, jointly with China, which when you think about it for a second is the only pairing it was ever going to be.

It's not called How To Make A Cup Of Tea. It's called Preparation of liquor for use in sensory tests.

They call the tea the liquor. Not the tea. There's no alcohol anywhere near it and nobody in the industry seems to think this is worth mentioning. The wet leaf left behind, meanwhile, is called the infusion, which is the word I'd have used for the drink. The entire vocab is inside out.

A document about tea that never once says the words "cup of tea" was trying to tell me something and I read straight past it. Here's what it actually says: two grams of leaf per hundred millilitres of water, tolerance of two percent. A pot of white porcelain or glazed earthenware, filled to within a few millimetres of the brim and brewed for six minutes. You then pour the liquor into a white bowl and tip the wet leaf out onto the underside of the lid so you can have a look at it.

If milk's involved, five millilitres for the large bowl, two and a half for the small one, and it goes in after the tea rather than before. Yeah I know what I've just started by even bringing that up.

There's an annex describing two pots in widespread use, at 310 and 150 millilitres, with matching bowls at 380 and 200. It contains engineering drawings of their cross sections. Somebody drew a technical elevation of a teapot and got someone else to check it before a committee actually signed it off.

There's a clause about your water too, It has to be about as hard as the tap water wherever the tea's eventually going to be drunk, and if you can't get hold of comparable water you're allowed to use distilled, but the document warns you in writing that your results will no longer bear a true relation to how the tea actually tastes.

In 1999 the British Standards Institution won an Ig Nobel Prize for Literature for it. The Ig Nobels go to work that first makes you laugh and then makes you think. It got revised again in 2019, so at some point a room of grown adults sat down and agreed the tea standard wasn't quite right yet. It's still in force now, and still not for drinking, which is the detail that actually got me.

The standard says so about itself, in the flat institutional voice of a document with no interest in being interesting. It isn't there to tell you how to brew tea for general consumption, it's there so meaningful sensory comparisons can be made, and that's when the rest of it stops being ridiculous and starts making sense. Tea's an agricultural crop, subject to rainfall, soil, altitude, and however the weather happened to go be that year. No two harvests give you the same leaf and no estate gives you the same thing twice. But the box in your cupboard has to taste identical every time, forever, or you'd clock it on the first mouthful and quietly start buying something else, and nothing closes that gap except actual people tasting the stuff.

Twinings master blenders taste up to 400 cups a day, sorting each one against 95 descriptors covering colour, viscosity, strength and character. It takes nine to twelve years to train one, which makes a tea taster slower to produce than a surgeon. Lipton has 79 of them spread across 15 countries, getting through something like a million cups a year between them. A working taster elsewhere in the trade might put away anywhere from 200 to 1,000 teas in a day. A single blend can be built from twenty components from different countries, adjusted continuously so the thing you taste never moves.

Around three quarters of the world's tea exports get sold at auction, on taste. Price bands are set by tasting. A man trys it, rolls it round his mouth, spits it into a bucket and puts a number on it, and then a huge amount of money changes hands. None of that's a figure of speech, there's an actual bucket, I promise.

So the taster is basically the measuring device. An uncalibrated measuring device is just a bloke with an opinion. If the brewing wobbles, whatever difference you're tasting between two teas might not even be in the leaf. Might just be in the pot. BUT Someone's just paid several hundred thousand pounds for a variable some random bloke introduced himself.

All of it's load-bearing. Six minutes, because five and seven are different teas. The pot dimensions, because thermal mass isn't a rounding error. The white porcelain, because a coloured bowl will lie to you about the colour of the liquor. The water hardness matched to wherever it's actually going to be sold, because a tea that tastes right in a lab in Hampshire and wrong in a kitchen in Stockport has failed at the only job it had. It's basically a calibration procedure you run on a human tongue.

Countries vote on ISO standards, and in the front matter of this one there's a line recording that one member body expressed disapproval on technical grounds, and that member body was Ireland. The only country on earth to have formally objected to the international standard for tea, on technical grounds, which means somebody in Dublin read the whole thing, weighed up the pot dimensions and the six minutes and the five millilitres of milk and the hardness of the water, and decided it was wrong.

They've never said what was wrong with it. As far as I can find, the grounds have never been published anywhere. The objection's recorded and just left there, and every printing since 1980 has carried it. Everyone's got a theory. Mine involves them just being awkward.

Somebody in Dublin read all of it in 1980, got to the end, and voted no. Forty-six years on, the objection's still sat at the front of the document with no explanation attached, and every teabag in your cupboard was signed off by a man with a bucket, brewing it the way the Irish said was wrong.