Low-VOC paint: what the label means and what it doesn't

What VOCs are

EPA describes volatile organic compounds as gases emitted from certain solids or liquids. Paints, varnishes and wax all contain organic solvents, and products like these can release organic compounds while you're using them and, to some degree, while they're stored. EPA also notes that concentrations of many VOCs are consistently higher indoors, up to ten times higher, than outdoors.

Some VOCs can affect health. Among the immediate symptoms some people have after exposure, EPA lists eye and respiratory tract irritation, headaches and dizziness. It's just as clear that the effect depends on the compound, the level and the length of exposure, and that not much is known about the health effects of the levels usually found in homes. That's a reason for sensible care, not alarm.

Paint isn't the only source in a house. EPA lists cleaning, disinfecting, cosmetic, degreasing and hobby products alongside paints, varnishes and wax, so a freshly painted room adds to what's already there. Stripping old finish is a different category. EPA says that during and for several hours after activities like paint stripping, levels can be 1,000 times the background levels outdoors, and it advises using products with methylene chloride, which includes paint strippers, outdoors when possible and indoors only with good ventilation.

Where the VOCs in paint come from

Paint is pigment and binder carried in a liquid. When the paint dries, the liquid leaves and the pigment and binder stay on the wall, and the leaving is where the fumes come from. In a water-based paint most of that liquid is water. In a conventional oil-based paint it's petroleum-based solvent, which is why Benjamin Moore says conventional alkyds carry higher VOC levels.

So choosing water-based over oil-based paint is one clear way to cut VOCs, and from there it's a matter of degree. Our post on latex versus oil-based paint covers the differences and where each one makes sense.

What the federal rule limits

EPA's national rule for architectural coatings, published in 1998, limits how much VOC manufacturers and importers can put into products like interior and exterior paints. The limits are measured in grams of VOC per liter of paint. For interior flat coatings the limit is 250 grams per liter, for interior nonflat coatings it's 380, and for primers and undercoaters it's 350. The count leaves out the water in the paint and any colorant added to tint a base.

Two details matter to a shopper. The rule applies to manufacturers and importers, not to consumers. And every can has to carry the VOC content of the coating, along with the date it was made or a date code, so the number you want is printed on the container.

What "low-VOC" and "zero-VOC" really mean

Neither phrase has one fixed meaning. EPA says the norms behind labels and certifications for indoor products aren't standardized, which makes it hard for a shopper to know what any one claim covers. It adds that some VOC labels are based on the VOCs regulated to control outdoor smog, so they can miss compounds that matter indoors, and it names paints labeled "low-VOC" or "zero VOC" as an example.

That doesn't make the labels worthless. It means the grams-per-liter figure is the thing to compare, and the phrase on the front of the can is the part to take lightly.

The tint problem

Color changes the number. In 2012 the Federal Trade Commission announced settlements with two large paint makers over "zero VOC" advertising. The agency said the claim may have been accurate for the uncolored base paint, but buyers generally get tinted paint, which may contain significant levels of VOCs.

Under the settlements, a maker that says its paint has zero VOCs needs sound science to show it contains none, or no more than a trace. Otherwise the maker has to say clearly that the claim applies only to the base paint and that the level may rise with the color. The takeaway for you is simple: ask for the VOC figure after tinting, for the color you're actually buying.

Ventilation does the real work

Whatever the label says, the steps EPA recommends are the same, and they're the ones that work:

• Increase ventilation when you use products that emit VOCs, and follow the precautions on the label.
• Open windows to bring in as much outdoor air as possible, and use an exhaust fan if the room has one.
• Keep ventilating after you finish. EPA says elevated concentrations can persist in the air long after an activity is over.
• Buy only as much paint as you'll use right away. EPA also notes that gases can leak even from closed containers, so don't keep old cans around.

In a Wisconsin November that means opening windows even when it's cold. Our post on painting in winter covers how to plan around the weather, and how to dispose of paint in Dane County covers what to do with the leftovers.

A plan for painting day

1. Before you buy, check the VOC figure on the can or data sheet, and ask whether it's for the base or the tinted color.
2. Open the windows before you open the first can, and run an exhaust fan if the room has one.
3. Close each can right after you pour, and keep cans out of reach of children and pets.
4. After the last coat, keep windows open and air moving, and give the room time before anyone sleeps in it.
5. When the job is done, dispose of leftover paint you won't use rather than storing it for years.

Choosing paint for your own job

When you hire us, your written quote is built around the paint you choose, and you can pick a brand other than the ones we usually use. If VOC level matters to you, say so on the estimate call and ask for the figure after tinting for your color. Floors and furniture are covered before any paint comes out, and interior painting jobs are priced by the square footage of the space, with paint included.

If anyone in the house is sensitive to fumes, say so on the estimate call, so George knows before the job is planned. A phone call comes first, and George visits if he needs to see the space.

For a bedroom or nursery, plan the painting early and leave time for the room to air out before anyone sleeps in it. Our post on nursery paint colors covers the color side of that decision.