millimetre of mercury

Name	Symbol	Quantity	SI units
millimetre of mercury	mmHg	pressure	≈133.322 Pa
The millimetre of mercury, symbol mmHg, is a non-SI unit of pressure. The millimetre of mercury is not accepted for use with the SI. One mmHg is approximately equal to 133.322 Pa.
Definition			h c^-3 Δν_Cs⁴
$1 \mspace{4mu} \text{mmHg} \mspace{6mu} \approx \dfrac{(133.322)(299 \mspace{4mu} 792 \mspace{4mu} 458)^3}{(6.626 \mspace{4mu} 070 \mspace{4mu} 15 \times 10^{-34})(9 \mspace{4mu} 192 \mspace{4mu} 631 \mspace{4mu} 770)^4} \mspace{6mu} \dfrac{h \mspace{4mu} {\Delta \nu _{Cs}}^4}{c^3}\\ \\ \\ 1 \mspace{4mu} \text{mmHg} \mspace{6mu} \approx 7.591 \mspace{4mu} 864 \mspace{4mu} 423 \mspace{4mu} 074 \mspace{4mu} 231 \mspace{4mu} 806 \times10^{20} \mspace{6mu} h \mspace{4mu} c^{-3} \mspace{4mu} {\Delta \nu _{Cs}}^4$