TVOC information TVOC means total volatile organiccompounds. For wet applied products (paints, coatings, adhesives,etc) TVOC levels are generally measured as the concentration ofVOCs in the product in units of g/liter. They are frequently listedin the MSDS (Material Safety Data Sheet) or technical specificationinformation provided by a manufacturer. For products that are notwet, TVOC is generally a measure of the total amount of VOCs thatconcentrate in the room due to emissions from the product and isgenerally measured by standardized lab tests (for example seeGreenGuard.
So called "Low VOC" products - particularly wet applied productssuch as paint or adhesives - usually base their IAQ claims on lowTVOC content in the product. The use of TVOC content is animperfect way to protect health from emissions from the productindoors since:
- there is no body of health science relating any particularlevel of TVOC content in a product to the presence or avoidance ofhealth impacts. There are hundreds of different individual VOCs, each that has different thresholds of observed health impact, often differing by several orders of magnitude.
- the TVOC regulations such as those promulgated by SCAQMD are aimed at controlling outdoor smog, rather thanprotecting indoor air quality. Hence the regulations exclude VOCsthat are not known to contribute to ozone/smog formation - althoughthey may still have other health effects. Therefore TVOC content inproducts is often solely the compounds that form smog, and may notinclude "exempt" compounds that may not cause smog but may haveother health problems.
- More VOCs can be formed during the curing of the product thatwere not in the product to begin with - including highly hazardousones, such as formaldehyde.
On the other hand, measures based on only individual VOC levelsmay also not fully indicate the potential health effects ofcombinations of multiple VOCs.And for wet applied products, there are problems with all currentlyproposed methods of measuring and rating emissions for healthimpact. Imperfect as it is, selecting wet applied products byseeking the lowest available TVOC content is the most healthprotective way to reduce the potential impacts of VOC emissions.