A pressure unit defined as exactly 1/760 of a standard atmosphere, which makes it 133.32 Pa or 1.333 mbar and almost exactly one millimetre of mercury. American tool makers, fabs and research labs read gauges in Torr and millitorr and quote leak rates in Torr·L/s. The name honours Torricelli, which is why the unit symbol is written with a capital T.
Heard on the job
Chamber's sitting at 2E-6 torr, give it another hour and we'll start the deposition.
Also heard as
- torr
Related terms
Millibar
One thousandth of a bar, equal to 100 Pa, and the default pressure unit in European vacuum work.
Pascal
The SI unit of pressure, one newton per square metre, used in standards and on calibration certificates.
Micron
Shop name for a millitorr, one thousandth of a Torr, used in US furnace shops, labs and refrigeration work.