Considering we spend 90% of our time indoors, isn’t it important to ensure the finishes used in our building interiors are safe? One such material that we are directly exposed to at all times is paint.
Paints were first seen about 30,000 years ago when they were used to decorate walls of ancient rock dwellings. Naturally available pigments such as charcoal, red and yellow ochre from minerals, and white from ground bones were mixed with binders such as water, animal fat, vegetable juice and even blood to enable easy application on walls.
The first paint mill was established in Boston, United States in 1700, but it was not until 1867 that the first ‘ready mixed’ paints were patented in the US.
What are VOCs?
Over the years, the paint industry has developed chemicals to enhance the properties of paint: colour effectiveness, drying time, ease of maintenance, shelf life and so on. These chemicals include volatile organic compounds (VOCs), which are organic chemicals that have a high vapour pressure at ordinary room temperature.
VOCs vaporise as soon as they are exposed to the atmosphere. As the material dries, it is the strong paint odour that lingers. In fact, this vaporisation can continue for years after application. Some of these VOCs include ethyl acetate, benzene, methylene chloride, etc., which lead to poor indoor air quality and are potentially harmful to human beings as well as the environment.
Long term exposure can put people at risk of developing ailments. At the ground level, these can lead to formation of smog, leading to poor outdoor air quality.
The good news is that the market now has several paint variants which come with low or zero harmful ingredients. Most of these are water-based paints which are odour-free and are made using natural materials such as clay, milk, casein and natural dyes.
International standards such as Green Seal-11, product certification systems such as GreenPro and green building rating systems such as LEED and Indian Green Building Council have specified limits for VOCs and other harmful ingredients in paints.
The VOC limit for indoor paints is 50 grams/litre. However, today there are many paints in the market that do not contain VOCs. It is important to look for this data while selecting the right paint for our buildings. The following labels can be used while selecting a paint: Green Seal Certified, Green-Pro Certified, or labels which note ‘zero or low-voc’. Similar precautions should be used while selecting other indoor finishes such as adhesives, sealants and varnishes.
The author is the founder of Green Evolution, a sustainable architecture firm