Measure and monitor air quality

Volatile Organic Compounds or VOC

Volatile Organic Compounds


What is VOC

VOCs or Volatile Organic Compounds are a large group of chemicals that are found in plenty of products we use to build and maintain our homes and buildings. Once they are inside a building they are released or ‘off-gassed’ into the indoor air we breathe. Sometimes you can also smell them … and smell is not a good indicator of good indoor air quality.

Common examples of VOCs that are present in our daily lives are: benzene, xylene, ethylene glycol, formaldehyde and methylene chloride. Typical sources are paints or varnishes, new carpets, adhesives, cleaning products, smoking, dry cleaning, photocopiers, building materials like foam and the burning of wood. VOCs are also emitted from humans and animals through breath, sweat and directly from their skin.


The effects of VOC

The risk of health issues from inhaling any chemical depends on the exact chemical compound, the concentration and the duration of the exposure.

Breathing in low levels of VOCs for a longer period in time may increase some people’s risk of health problems, especially persons with asthma or particularly sensitive to chemicals. Since VOCs refer to a group of chemicals, each of them has its own toxicity and potential for causing different health effects. Breathing in high levels of VOCs is known to cause eye, nose and throat irritations, headaches, drowsiness, nausea, reduced concentration and fatigue. In the long run it can lead to cancer and damage to the liver, kidney and the central nervous system.


Reducing VOC

To protect your health, it is best to limit the exposure to products and materials that contain VOCs. The best way to reduce VOC levels is to avoid them in the first place. Inspect the building or your home for the common sources of VOCs. Only buy and keep the paints, detergents and adhesives that you need. If you need to store them, do this in a place where people do not spend much time so that when they leak, they cannot harm anyone.

Sometimes you cannot avoid VOCs – especially during remodel or renovation work. When you cannot avoid them, increasing the amount of fresh air brought into the space helps to reduce the concentration of VOCs indoors. You can do this by opening windows and doors or by using fans to maximize air brought in from the outside. Keep the temperature and relative humidity as low as possible because chemicals off-gas more in high temperature and humidity.

Typical VOC sources


TVOC sensor

If you want to be sure if the air quality is ‘safe’ you can monitor this with a special VOC sensor. The Sentera TVOC sensors measure, apart from temperature and relative humidity, the total amount of VOCs in the air with a high selectivity to hydrogen (H2). In indoor environments, the H2 concentration is expected to correlate well with the CO2 concentrations, as human breath contains significant concentrations of both CO2 (4 %) and H2 (10 ppm). This makes it possible to distinguish the influence of human presence from other contaminants and control the ventilation system based on the occupation of a space. Our sensors will inform you, via LED and/or buzzer when the VOCs in the space have reached an alarming level and ventilation needs to be increased to extract the contaminated air from the area. Typical applications are fitness rooms, waiting rooms, night clubs and restaurants as well as production halls of paints etc.