Common Vacuum Scale (left scale - lower part)

This scale is also shown on the left side. Note that the scale begins at zero (0) indicating no vacuum and extends to 29.92 in Hg.

This scale extends from 0 to 29.92 in Hg.

Zero (0) vacuum is the same as atmospheric pressure (or 0 psig).

Total vacuum (complete removal of air and other gasses) is indicated by 29.92 in Hg. This is shown at the bottom left side of the scale.