PID lamp for gas measurement

Gas measurement is divided into two main areas:

  • Portable VOC detectors
  • Gas chromatography

In both methods, PID lamps (photoionisation detector lamps) play an important role.

PID lamp for gas measurement

PID lamps emit high-energy photons in the VUV range of the spectrum. These photons ionise any gas that has an ionisation potential lower than the photons' energy and generate positively charged ions. If ionisation takes place within the electric field between two electrodes in the sample cell, a measurable current is generated which is proportional to the concentration of the gas. PID lamps provide an efficient, inexpensive and immediately usable method for measuring volatile organic compounds (VOCs) and other gases in concentrations from the ppm to the ppb range.

Portable detectors are normally not gas-selective and determine the total concentration of VOCs. However, they can be made more selective by choosing a suitable light source.

Gas chromatography is gas-selective and more elaborate because the individual components of a gas mixture are separated in a separating column before each constituent gets into the sample cell to be detected there.

Typical applications for environmental analysis

  • Air analysis
  • Pollutant monitoring

Monitoring BTEX compounds (benzene, toluene, ethylbenzene and xylenes) using PID lamps is an economical way to monitor the air quality in cities or to detect hazardous substances for hazard defence teams, public safety and military protection.

Typical applications in the chemical and petrochemical industry

  • Chemical analyses
  • Monitoring of BTEX compounds (benzene, toluene, ethylbenzene and xylenes)
  • Pollutant monitoring
  • Detection of VOCs in closed rooms
  • Leak detection in oil and gas production

Monitoring BTEX compounds using PID lamps is an economical way to warn of fire risks, provide personal protection in the petrochemical industry and monitor general air quality in industrial areas. Detection of hydrocarbons such as ketones, alcohols and esters ensures a safe working environment in both industry and the office.

Typical applications in shipping

  • Pollutant monitoring
  • Detection of VOCs in closed rooms

When cleaning and repairing large accessible tanks and containers, residues of the aforementioned substances may pose a high risk. In the case of BTEX compounds or other volatile organic compounds (VOC), there is an explosion hazard in addition to the substantial health hazard. It is therefore important to constantly monitor the VOC concentration while inside the tank or container to prevent accidents and ensure a safe working environment.