Minnesota Gov. Mark Dayton signed a bill into law that will require carbon monoxide detection systems on certain recreational boats.

As of May 1, 2017, such a system will be mandatory on any motorboat that has an enclosed accommodation compartment. Additionally, no new boat with such a compartment can be offered for sale after that date in Minnesota unless it is equipped with a CO detection system.

The National Marine Manufacturers Association said the definition of enclosed accommodation compartment in the new law aligns with the standards of the American Boat & Yacht Council: a contiguous enclosed space surrounded by a boat structure that has designated sleeping accommodations, a galley area with a sink, and a head.

The NMMA also said the new law’s definition of a CO detection system is in line with the ABYC standard. Minnesota is believed to be the first state in the country to require CO detectors on boats.

John Adey, president of the ABYC, said the new law is “a knee-jerk reaction to a very bad accident,” but he was pleased with the way the bill developed and with the cooperation the ABYC received from Minnesota lawmakers, including state Sen. Melisa Franzen, sponsor of the Senate version.

“She was terrific,” Adey said. “She was open to everything we had to say.”

Adey said Minnesota lawmakers were not previously aware that the ABYC had developed equipment and installation standards for CO detectors on boats.

Minnesota’s new requirements were known as “Sophia’s Law” as a standalone bill. The CO detector provisions passed as part of a much larger state appropriations and policy measure.

Sophia Baechler was 7 when she died of carbon monoxide poisoning during a family outing on Lake Minnetonka last October.

The Minneapolis Star Tribune said at the time that there was a hole in the exhaust pipe in the boat’s cabin, where Sophia was resting. The Hennepin County Sheriff’s Office told the newspaper that the hole was beneath the mattress area in the lower cabin area and probably was caused by animals that chewed through the pipe.

The newspaper said CO poisoning fatalities from a boat had occurred only twice in Minnesota during the previous eight years. Toxic and odorless, the gas can build up because of an idling motor, a generator or a faulty exhaust system.

“Carbon monoxide poisoning is a silent killer that can be deadly within minutes,” Franzen said when the Senate passed the bill. “While carbon monoxide detectors are common in homes, many people may not think to have them on their boats — a risk that can lead to tragic accidents.”

The NMMA said the bill also requires CO poisoning warning stickers on all boats 19 feet and longer in the aft reboarding area, the galley and the steering station for all new or used motorboats that are gas-powered.

The state Department of Natural Resources will mail the stickers to boaters during the registration process.

Dealers will be required to ensure that warning labels are affixed to boats before sales are completed.

The law also will require that all state-sponsored boating safety courses and all safety courses that require state approval provide information about the dangers of being overcome by carbon monoxide poisoning on a boat and how to prevent it.