What’s a TVOC?
TVOC is an overall measurement of the total chemical concentration in the air.
The most common contributors to TVOCs are:
- odorants (think Pinesol)
- personal care (think shampoo, perfume, scented soap)
Gasoline has six “marker compounds” associated with it. They are benzene, toluene, ethyl benzene, and the three xylene isomers. The source of gasoline can be ambient air (especially in urban environments) but it is generally the office occupants themselves who supply the contamination. Remember that for every gallon of gas pumped into an automobile, one gallon of air saturated with gasoline vapor is dumped into the lap of the person filling the tank. This person then goes to the office or home and off gasses the rest of the day. The gasoline levels in homes are generally higher than in offices because, in addition to the personal off gassing, the most common source of gasoline vapors is the collection of gas cans, mowers, trimmers, etc. in the attached garage.
Paints are very complex and can have several different markers but typically they include methylcyclohexane, substituted cyclics, butylcellosolve, substituted alcohols, unsaturated C9-C12 hydrocarbons, and the straight-chain hydrocarbons nonane (C9) through dodecane (C12). Paint VOCs can linger at significant levels for as long as 18 months after application; however, even though the paint may be fully cured, leaking paint cans often contribute to the VOC load for years.
Odorants are chemicals that are supposed to smell good. They are in air fresheners, potpourri, scented oils, perfumes/colognes, and nearly all cleaning and personal care products. In a typical office, especially in an office or home where an IAQ problem exists that the occupants think they can eliminate by covering it up, odorants can make up a significant fraction of the TVOC load. These odorants include many aldehydes, alcohols, ketones, pinenes, and complex esters.
Personal Care Products
Personal care products are the primary source of acetone. Acetone is typically associated with nail care (nail polish remover is nearly 100% acetone). Other compounds associated with personal care include the C2-C5 acetates (nail care), isopropanol, and ethanol (cosmetics and hair spray), and menthol, camphor, and methylsalicylate (topical ointments).
Lifestyle chemicals are many and varied but the three primary compounds are ethanol from antiseptic wipes (although the occasional leaking bottle of scotch cannot be ruled out), tetrachloroethylene or PCE, from garments that have been dry cleaned, and 1,4-dichlorobenzene from mothballs.