Toxic volatile organic compounds (TVOCs) are a group of carbon-containing compounds with a high vapor pressure in air. There are many VOCs emitted from daily activities, some of which are colorless, some are odorless and some are toxic. Therefore, TVOC monitoring is an effective way to detect exposure to toxic VOCs. Life is in constant contact with a number of products containing and/or emitting VOCs, e.g. disinfectants, paints and varnishes, solvents, semiconductor materials, rubber, vehicle exhaust, fuels, inks printing, adhesive, etc So each VOC has its own characteristics. For example, due to combustion, car exhaust gives off ethylene while broadleaf trees give off isoprene. Different VOCs have different reaction rates and, therefore, have a large transport distance when emitted. VOCs that persist in the atmosphere for a long time are known as Persistent Organic Pollutants (POPs) and some VOCs are known as Hazardous Air Pollutants (HAPs) because of their toxicity.
