100 years DIN A4 formatCurious standards from tea to clay
Tea is quickly made in everyday life. But not when it comes to ISO standard 3103. Here, the process is explained in great detail over six pages. You can read these and other strange guidelines here.
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© Karl-Josef Hildenbrand/dpa
One of the most unusual standards is ISO 3103, which deals with the question of how to make a perfect cup of tea.
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