It's been 10 years since the Federal Trade Commission's"Guides for the Use of Environmental Marketing Claims" (aka the "Green Guides") were last updated, a decade during which the importance, and commercial value, of environmental claims for various products has skyrocketed. Hundreds, if not thousands, of building materials, packaging choices, and manufacturing options have come onto the market. And phrases that have become common parlance since 1998—such as sustainability, renewable energy, and carbon offsets—have not yet been addressed by the FTC.

In January the agency took the first step to rectify that, a move that ultimately will give consumers, including architects and builders, a more concrete idea of what manufacturers and others should mean when they offer a carbon offset in order to enhance the "greenness" of products. (In essence, carbon offsets are a way of mitigating greenhouse gas emissions through actions such as planting trees, investing in renewable energy providers, and the like.)

At a January public workshop on green marketing claims, the FTC heard from more than two dozen experts on the subject. Eventually, says the FTC's Hampton Newsome, the agency is currently considering whether to issue guidance on the subject—not a definition of carbon offsets, but examples of when an advertisement for carbon offsets could be misleading.

"Our job is deceptive claims, not what environmentally friendly policy is," adds Newsome, an attorney in the enforcement division of the FTC's Bureau of Consumer Protection. "The basic rule of the road at the FTC is that marketeers have substantiation to back up their claims. And they also have to substantiate claims that are implied."

For example, the FTC says in its current Green Guide, if an aerosol product boasts that it does not contain any ozone-depleting chlorofluorocarbons (CFCs), but in fact contains another ozone-depleting ingredient, then the claim is deceptive because a reasonable consumer would assume the product does not harm the ozone layer at all.

The comment period for suggestions on determining a deceptive advertisement for carbon offsets ended on Feb. 11. If the FTC decides to add its advice on carbon offsets to the Green Guides (which can be found at, there will likely be a second public comment period before carbon offsets are officially added, says Newsome.