The torr is a unit of pressure commonly used in scientific and engineering contexts to measure low-pressure conditions. It is particularly valuable in vacuum technology and gas-related applications, providing a way to express pressure in a range where standard atmospheric pressure isn't suitable.

Definition and Usage

The torr is defined as 1/760 of a standard atmospheric pressure. This makes it equivalent to 133.322368 Pascal (Pa) and provides a practical way to express low pressures that are often encountered in vacuum systems and research settings.

Importance in Vacuum Technology

The torr plays a crucial role in various fields:

  • Vacuum Systems: Engineers use torr to measure and control pressures in vacuum technology.
  • Chemistry and Physics: It's used to study gas behavior under low-pressure conditions.
  • Medical Research: Torr is used in applications like gas chromatography and mass spectrometry.

Conversions and Equivalents

Understanding how to convert torr to other pressure units is important:

  • 1 Torr = 133.322368 Pascal (Pa)
  • 1 Torr ≈ 1.315789 x 10^-3 Bar
  • 1 Torr ≈ 1 mmHg (millimeter of mercury)
  • 1 Torr ≈ 0.0193368 psi

Practical Use Cases

Torr measurements are used in a variety of practical applications:

  • Vacuum Chambers: Engineers use torr to indicate and regulate pressure in vacuum systems.
  • Gas Analysis: Torr is used in gas analyzers to quantify gas concentrations.
  • Leak Detection: It aids in identifying leaks in vacuum equipment.


The torr unit is essential for measuring low-pressure conditions encountered in vacuum technology, research, and various scientific fields. Its role in expressing pressure values under conditions where standard atmospheric pressure isn't applicable makes it a valuable unit for professionals working with gases and vacuum systems.

Keywords: Torr, pressure unit, vacuum technology, gas behavior, conversions, vacuum systems