airpointer®Volatile Organic Compounds (VOC)
VOC (Volatile Organic Compounds) are not a specific pollutant but a class of chemical compounds which are present almost everywhere (e.g. acetone, benzene, toluene, cyclohexane, n-hexane, formaldehyde, styrene, chlorinated solvents, and several other organic solvents). Some of them are non-toxic and many are noxious. You can observe high pollution levels especially near (petro)chemical industry and whenever fuel is not completely burned. Almost all VOC can be detected by a PID sensor. In ambient air, the reading of a PID is not to be understood as current concentration since its response is specific to each VOC compound. Nevertheless, the reading gives a good idea of the VOC pollution run. The VOC module is ideally suited for the detection of fugitive emissions and fenceline monitoring and suited even for the relatively low concentrations in ambient air.Health and Environmental Effects
The ability of organic chemicals to cause health effects varies greatly from those that are highly toxic to those without known health effects. As with other pollutants, the extent and nature of the health effect will depend on many factors including level of exposure and length of time exposed. Eye and respiratory tract irritation, headaches, dizziness, impaired vision, and memory impairment are among the immediate symptoms that some people have experienced soon after exposure to some organics.
Source: US EPA www.epa.gov Indoor Air QualityVOC and the airpointer®
PID (Photo Ionization Detection)
VOCs are ionized by a UV lamp. The ions migrate into an electric field to discharge electrodes. By discharging, an electric current is produced which is used as a measurement signal.
| Component | Principle of Measurement | Range | Unit |
| Volatile Organic Compounds (VOC) | Photo Ionization Detection (PID) with special long life 10.6 eV UV lamp | 0.01 ppm to 20 ppm isobutylene equivalent | ppm |