Are glucose level reported surrounded by different breadth jargon surrounded by Europe and U.S.?

Someone from Germany told me that he checks his sugar several times a day and 600 is a dutiful number for him. I know in U.S. language, 600 is a dangerously big number.Are glucose level reported surrounded by different breadth jargon surrounded by Europe and U.S.?
I'm only aware of the two as powerfully. Here's a handy converter:
Blood glucose converter:
http://www.brist.plus.com/convert.htm...
Glucose level is measured within mm/litre (millimoles per liter in most countries) and mg/dL (milligrams per deciliter within the U.S.) To convert one to the other, you multiply it by 18. A level of 6 is 6x18=108 contained by the U.S. I am not aware of other measures. 600 is a very huge number. Germany may be using a different guess, I don't know.
That can't be right.
Germany does use the mg/dl system as does the US.