The rules around the increasingly popular electronic cigarette remain murky, but one industry isn’t afraid of doing a little self-regulation.

Last week, the National Association of Convenience Stores (NACS) announced that it would encourage its members—who participate in a $700 billion-per-year industry—to be proactive about restricting e-cigarette sales to minors by using the age-verification practices already in use for sales of alcohol and traditional tobacco products. The association issued its guidelines on Thursday.

“Given the uncertain status of e-cigarettes, it just makes sense that convenience stores check IDs as part of the more than 4.5 million age-verification checks that we already conduct every day,” NACS President and CEO Henry Armour said in a statement.

The Food and Drug Administration has yet to formally regulate the products, which heat a liquid nicotine solution and produce a smoke-like vapor. Because the devices do not contain tobacco, they are not currently subject to FDA rules—a loophole that allows the products to be sold to minors. The FDA is expected to close that loophole, according to the Associated Press. Meanwhile, several states have prohibited the sale of the products to children and teens.

NACS says the convenience store industry was responsible for $540 million in e-cigarette sales in 2013, representing 75 percent of all brick-and-mortar sales outside of kiosks and tobacco stores.

The NACS move comes at a time when retail chains and city governments are pushing for stronger regulation of traditional tobacco products. Earlier this year, CVS became the first major pharmacy chain to announce it would stop selling tobacco products, and New York City approved a ban last year on using e-cigarettes indoors.

(Sean Gallup/Getty Images News/Thinkstock)