|Auxiliary unit of measure
|Per mille, thousandths
|Italian per mille , "from the thousand"
|See also: percent , ppm , ppb
A per mille (composed of the Latin pro 'in proportion to' and the Latin mille 'thousand' ) or thousandth stands for the fractional number 0.001. Per mille information is usually indicated by the alcohol symbol ‰ .
The basic equation applies:
This results in:
as well as the formula that can be used as a calculation control:
Banking and insurance
Alcohol in traffic
The term per mil is colloquially related to the alcohol content in the blood of the respective person. The blood alcohol content is usually given in per mille and can be calculated using the Widmark formula and measured in the breath or in the blood. The unit of measurement is the mass ratio of milligrams of alcohol per gram of blood (mg / g) - see article Blood alcohol concentration . With a handy Alcotest device, which is usually used on the street during police checks or during accident recordings, and into which one blows, it is possible to determine the alcohol concentration in the breath of the person concerned. The unit of measurement is the amount of alcohol in milligrams per liter of breath (mg / l). For example, the value 1.0 mg / l breath alcohol concentration corresponds approximately to a blood alcohol concentration of 2.1 mg / g, i.e. 2.1 per mille. The exact alcohol content - should it be suspected to be too high - is then determined at the police station either with a much more complex breath alcohol measuring device or by a doctor with a blood alcohol measurement (with a small amount of blood drawn from the person concerned).
Inclines / slopes of railway lines
While the inclination is usually given in percent for roads , the horizontal inclination of stretches for adhesive webs ( gradients ) is given in per mille. The value corresponds to the difference in height in millimeters per meter of horizontal distance (or the difference in height in meters per kilometer of distance), i.e. the tangent of the angle of incline. The value is required to calculate the maximum possible towing weight or the trailer load on inclines, and also to determine the maximum permissible speed on slopes (depending on the braking force and towing weight).
Routes with a gradient of more than 50 ‰ can usually only be traveled with the help of a gear drive. Exceptions are e.g. B. Lisbon's tram , the maximum gradient of which is 13.5%, i.e. 135 ‰, the Pöstlingbergbahn in Linz with 105 ‰, the Uetlibergbahn with 79 ‰, the Bernina train with 72 ‰ and the Erzbergbahn with 71 ‰.
In the German standard DIN 5477 of February 1983, details on the correct use of the per mille are specified. Accordingly, its use is restricted to the use of "the specification of quotients of numbers or sizes of the same dimension including money". In the international standard ISO 80000-1 ( sizes and units , Chapter 6.5.5) from August 2013, per mil is used "as part of the coherent unit one "; the symbol ‰ is used like a unit symbol. According to DIN 5008 , the substitute representation "o / oo" (with lower case letter o ) is possible in text works .
Enter / key combinations
- German standard keyboard layout E1
- - 5
- macOS (Germany keyboard)
- ⌥ Alt+ ⇧ Shift+E
- macOS (Swiss keyboard)
- ⌥ Alt+ ⇧ Shift+§
- Linux, Unix
- Strg+ ⇧ Shift+ U+2030
- DIN 5008 : 2020-03 Writing and design rules for text and information processing , section 10.7 percent and alcohol symbols