About 300 Hawaii workers in the nation’s most deadly industry gathered Friday on a lot in Kakaako to recognize the importance of protecting themselves from the leading cause of death in their business.

The early-morning gathering was arranged by three construction companies erecting condominium towers at Ward Village, and included a demonstration of how falling off a high place — even when tethered to a safety line — can disable or kill.

“Take it to heart today: You only get one chance,” Nate Lutz, supervisor of health and safety at Nordic PCL, told the crowd after it was noted that 350 people in the construction industry nationwide died from falls in 2015, or nearly one every day. “You do not want to be that one person.”

The demonstration included showing what kind of impact a 200-pound worker harnessed to a taut safety line would suffer falling just 10 feet, and it was quite a shock: 3,600 pounds of force, to be exact, which is enough to wreck internal organs or perhaps break a back or worse.

Representatives of safety equipment manufacturer 3M demonstrated such a fall by dropping a 200-pound weight connected to a safety line suspended from a hoist.

Such taut safety lines were outlawed by the federal government in the 1990s, and now lines containing shock-absorbing extensions are standard. 3M repeated the demonstration with a shock-absorbing line and also a more advanced safety line that feeds out and can stop a fall within two feet of descent while also reducing the force of shock on a body to about 600 pounds.

Lyndon Talanoa, a carpenter working on the A‘eo tower, said the reminder about fall dangers was good. “Definitely, because it’s something you might not come back from,” he said.

Six people in Hawaii’s construction industry died in 2015, according to the latest data from the U.S. Bureau of Labor Statistics released last week. That was the most for any industry. Among all industries, which accounted for 18 deaths in Hawaii in 2015, falls were the third most common reason after transportation and violence or injury caused by persons or animals.

The state Department of Labor and Industrial Relations recommends that all employees who work on equipment or structures 6 feet or more above ground be trained in fall prevention and use a fall protection system. The agency also recommends that companies provide body harnesses and safety lines for workers and then also check routinely to ensure safety procedures are being followed.

Fall risks in the industry always exist but are elevated now amid a local construction boom that extends beyond condominium towers. DLIR, which encourages everyone in the industry to focus on safety, has publicized local case studies that include a painter who was killed in 2006 from a 20-foot fall off a townhouse roof and a roofer who broke his pelvis and an elbow in 2008 when he fell 24 feet through a fiberglass panel serving as a skylight on a corrugated metal roof. Neither worker was wearing a safety line, according to the agency.

Friday’s demonstration was organized by Nordic PCL, Albert C. Kobayashi Inc. and Layton Construction Co. to participate in a national campaign by the U.S. Department of Labor’s Occupational Safety and Health Administration to raise awareness of fall hazards and safety in the construction industry. OSHA said 350 of 937 construction fatalities nationally in 2015 were due to falls.

“That’s not acceptable, guys,” Vern Miller, site safety supervisor with Layton Construction, told the group in Kakaako after reciting that statistic. “We should not even have one fall.”