Photoionization detector

A photo-ionization detector (abbreviation: PID) is a device for the detection and analysis of chemical compounds in the surrounding air. For example, aromatic hydrocarbons, some common solvents and a variety of different inorganic, but particularly organic substances can be detected.

Principle of operation

A photoionization detector aspirated by means of a pump, the ambient air and converts them to the UV light of a gas discharge lamp. When ionizable substances are present in the air, this is indicated as a concentration in the display.

Technical use

PIDs are used for example for leak detection, in the measurement of pollutant concentrations in accidents in the monitoring of a decontamination site or the load of the ambient air by outgassing pollutants.

Mobil, a PID is installed, for example, on the ABC exploration vehicles of the civil protection and can be converted in a few steps to a portable device. In other applications, smaller hand-held devices are used, which can be aligned by means of special bets on a pollutant class.

The PID is used as a specific detector for the gas chromatography.