Paint: Working Toward Lowering VOCs, Raising Performance

Paint can literally transform a room, giving it personality, warmth and energy - and a well-painted room can be a visual joy. With an ever-expanding palette of colors and finishes, manufacturers are steadily increasing the options of how today's surfaces can be decorated for effects that range from traditional to sophisticated to super-chic.

The LEED Gold Hearst Corporation headquarters in New York City used zero-VOC latex paint in most of the interior space. Photos courtesy of The Sherwin-Williams Company.

 

Just as paint technology is increasing visual options, the paint industry has been working to improve the health and environmental quality of their products since passage of the Clean Air Act in the 1970s. Today's paints promise environmental quality without sacrificing performance.

Regulations on volatile organic compounds (VOCs) have helped move these formulations to more environmentally responsible coatings. Technology from raw material suppliers and coating manufacturers has advanced to allow the design of a low VOC coating with performance attributes such as hiding (covering the surface), washability (stain removal) and scrubability (abrasion resistance). VOCs, the ingredients used as solvents, can give paint a pungent smell. VOCs can "off-gas" from the walls into the air as paint is applied and as it cures, though once paint is fully cured, no more VOCs are released.

Not all paints contain equal amounts of VOCs. Oil-based paints tend to contain more VOCs than water-based or latex paints; white or lighter-colored paints have less VOCs than brightly colored or dark paints, due to the colorant used in tinting. Regardless of the absolute level of VOCs in paint, when a home or other building is painted, occupants have greater than normal exposure to VOCs - as much as 1,000 times greater. According to the American Lung Association, VOCs can produce breathing problems, headaches, nausea, liver and kidney damage, skin and eye irritation. And, with indoor applications, VOC impact spills over from the immediate area to the environment, potentially causing smog and ozone depletion. According to the EPA, as much as nine percent of smog-forming pollutants come from VOCs in paint.

Over the past decade, local, state and federal regulations have curbed VOC levels in paint and other household products, spurring manufacturers to produce low- and no-VOC paints that release no, or minimal VOC content , and are virtually odor free. "The VOC regulatory arena is a complex and ever-changing situation," says Sherwin-Williams Director of Marketing Steve Revnew, explaining the main actors are the U.S. Environmental Protection Agency (EPA), an advisory group created under the Clean Air Act of 1990, the Ozone Transport Commission (OTC), the South Coast Air Quality Management District (SCAQMD) and the California Air Resource Board (CARB), with the most stringent restrictions coming from SCAQMD. Currently, under ASTM method 24, the EPA defines no-VOC paint as containing less than 5 grams of VOCs per liter. But caveat emptor: the paint may still use colorants that have VOCs - and the addition of a color tint can ratchet up the VOC level on average up to 10-20 grams/liter, though that level is still considered low. It is very difficult to determine the VOC of a tinted product, as the total VOC is dependent on the type and amount of colorant used. Revnew cautions that it is always best to simply start with a low- or no-VOC product, as stated on the label - that alone will make a significant contribution towards being environmentally responsible. It is also advisable to keep in mind that, in general, lighter colors will contain less colorant than darker colors. The manufacturer can provide the material data sheet (MSD) with VOC ratings for the chosen pigment to verify LEED criteria.

Low-VOC paints were used in Indianapolis-based Innovative Design Offering's (i.d.o.'s) offices, which were designed to be a model of green building. (For more details, see the "Getting To Green" section on p. 5 of this article.) Photos courtesy of The Sherwin-Williams Company.

 

Generally speaking, low-VOC paints, stains and varnishes use water as a carrier instead of petroleum-based solvents, with lower levels of harmful emissions than solvent-borne surface coatings. Today, nearly 80 percent of paints in the residential market are water-based paints, according to government shipment data.

Designations of "low-VOC" status vary. Currently, the EPA limits VOCs in paints to 250 grams per liter for flat finishes and 380 grams per liter for other non-flat finishes. The OTC takes it a step further, defining low VOC as less than 100 grams per liter. While the OT C recommendations are voluntary by state, once a state has chosen to adopt them, restrictions are binding. Many states, particularly in the Northeast, have already done so - a move which has the effect of limiting the sale of oil-based paints, which have higher VOC contents. The EPA failed to pass federal standards based on the OTC recommendations in the summer of 2008, as was widely expected, though the standards may be enacted in 2010. If passed, the standards will signal the death knell of oil paint, once the heavily preferred choice of painters of architectural surfaces. California takes the issue even further, restricting the VOC content to less than 50 grams per liter - a standard to which some manufacturers are already adhering.