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Numerical value Limit Value in ppm β
Numerical value of the Limit Value in ppm
The number or numerical value of the limit value in parts per million. This dimension is, although not an SI-unit, used worldwide for substances or mixtures of gases or fumes in the workplace atmosphere.
If no limit value in ppm is given, it is converted (if the molecular weight [MW] is known) from mg/m3 to ppm.
This conversion is done with the formula: X (mg /m3) = Y (ppm) * 22.4/MW.
In the field Dimension of the Limit Value the dimension "mg / m3 (* 22.4/MW=ppm)" is given to indicate that the value in ppm has been calculated.
