When Aimee Copeland prepared for a ride on a homemade zip line in a friend’s back yard near Carrollton several weeks ago, the University of West Georgia graduate psychology student did what millions of people do annually.

The practice of zipping through and above nature on a line suspended in air and tied to surrounding trees or stands has become one of the most popular outdoor activities in Georgia and other parts of the country.

The line that Copeland was riding over the Little Tallapoosa River on May 1 was attached to a low bluff, rising perhaps 6 feet above a rock bank. The line snapped on the 24-year-old woman’s second ride, sending the nature-loving Snellville native onto the rocks beneath and leaving her with an injury that has become life-threatening.

Copeland’s struggle for survival at an Augusta hospital has captured the attention of zip line enthusiasts around the world, and the notice of a booming industry that insists accidents are rare – if safety is paramount.

Conservatively, at least 18 million people ride commercially operated zip lines annually, according to the Association for Challenge Course Technology. In the absence of state regulations, the group sets standards for an estimated 250 commercially operated zip line businesses in the U.S. ACCT also accredits zip line builders and inspectors.

Although zip lines have been a part of outdoor challenge courses for decades, commercially operated zip lines are a relatively new industry, with the first appearing around early 2000. From Valdosta to the North Georgia mountains, there are at least a dozen in Georgia.

“The industry is growing exponentially,” said James Borishade, executive director of the Deerfield, Ill.-based ACCT. “There are several new zip lines going up each month.”

No federal laws or state regulations in Georgia deal specifically with zip lines. Amusement businesses, however, must follow industry inspection standards, such as those provided by the ACCT, which is the largest of two that specifically accredit zip line builders and inspectors. The other group is Professional Ropes Course Association.

Borishade said accidents due to snapped lines or other problems are rare at commercial attractions, where patrons pay a fee to ride. Most, if not all, of these attractions undergo annual inspections by qualified challenge course professionals in accordance with ACCT or similar standards.

Historic Banning Mills in Whitesburg, “Home of the Screaming Eagle Zip Line,” is among the businesses that submit to ACCT-backed annual inspections and daily staff inspections, according to founder Mike Holder.

Holder said his west Georgia zip line business has experienced a drop-off in patrons, including reservation cancellations, because people wrongly assumed the Copeland accident occurred at Banning Mills, about 30 miles southeast of the accident site near Carrollton.

Holder, who built zip lines as an Army Ranger, said there has never been a major accident at Banning Mills. His zip line attraction, the largest in the country, has 50 cables that are made with half-inch-thick steel rope. The lines, which can hold 20,000 pounds, also have several backup cables to ensure safety.

Holder expects business to pick back up when people realize the accident occurred miles away.

Jeff Manley, general manager of The Rock Ranch, said safety was already paramount at the Middle Georgia attraction, which opened its own zip line a year ago 38 miles north of Macon. The Carrollton accident, however, was a reminder that businesses can’t be too overly cautious.

The Rock Ranch’s four Cow-a-Bunga Zip Lines have attracted thousands of visitors, many from metro Atlanta. Manley said the lines are inspected twice a year by licensed engineers, and cables are replaced after 5,000 “zips” even though they are “strong enough to pull a tugboat.”

No one under age 18 can operate a zip line at Rock Ranch, and staffers must have at least eight hours of training to be zip line operators.

“I feel like we’re almost paranoid in our safety efforts,” Manley said, but he added it’s necessary to go the extra mile.

Manley urged consumers to ask safety-related questions, such as frequency of inspections, when considering a zip line operation.

“Be an educated consumer when looking for these adventure activities,’ Manley said. “Anybody can throw up a zip line. If people can’t answer the questions, you might want to consider another location.”

Borishade, of the ACCT, also suggested that people who have zip lines erected by anyone other than a professional are putting themselves and others at risk.

“We do not accredit any builder that sells homemade back yard zip lines because we are advocating for zip lines to be designed and installed by a qualified challenge course professional,” Borishade said.

While zip line kits are not available at large sporting goods stores like Sports Authority or REI, they can be purchased online and can cost as little as $49 for a 35-foot assembly or more than $500 for more elaborate kits. The packages can include cable and hardware, trolleys, seats, harnesses, braking systems and other accessories.

“We believe it is absolutely critical for any zip line to be installed by a qualified challenge course professional,” Borishade said.

And, like flying, zip lining “is very unforgiving if you don’t do it right,” said Holder of Banning Mills.