Transcript for Carbon monoxide poses risks for boaters
We are back now with a summer warning about boats. Thousands currently in the water could carry the danger of carbon monoxide poisoning. ABC's gio Benitez is off the coast of New Jersey with the details. Good morning, gio. Reporter: George, good morning to you. Listen, carbon monoxide poisoning on a boat is just something we don't think about but some states like Minnesota are already working to change that and that's because as you're about to see, it could be deadly so this morning, "Gma investigates." 16-year-old raven little white loves spending time on the water but in 2016 after hanging out on a boat swim platform while on a North Carolina lake she fell into the water and drowned. A toxicology report later blamed carbon monoxide poisoning. Sometimes it can be very high levels of carbon monoxide. Reporter: This summer through a new outreach program raven's rule named after the teen north Carolina wildlife officials are warning boaters about the dangers of carbon monoxide poisoning. A lot of folks are not informed on this topic. We've encountered this on a regular basis. Reporter: Co poisoning contributing to 14 deaths in the last two years. Experts say the problem is that in some boats when the engine is running exhaust can collect around the back of the boat, boats built after 2011 are likely to have a converter that limits harmful gases from the exhaust. But there are still thousands of boats without this technology that are on the water. Everybody says, oh, I'm out on the boat all day. I have a headache because of the sun, beer, not drinking water. When really it could have been co. Reporter: To show how quickly levels can rise we hit the river in Maryland with this 2002 ski boat and John Adey with a nonprofit that sets industry standards for boats. There's the meter. I put on a carbon monoxide meter to see if high levels reach the backseating area of that boat. John holds another meter over the swim platform. The most dangerous area of the boat. Zero parts per million. Reporter: The alarm will go off when it detects a toxic amount of co in the air which John says can be harmful with as little as 15 minutes of continuous exposure. Okay. So it's going off right now. Right. Less than two minutes in the alarm sounds. So what's the danger zone. Well, it's time versus exposure level. So it's really a time thing. Reporter: Nearly 20 minutes into our demo. My meter alarm detecting dangerous levels in the back of the boat where anybody might seat. John says the wind is more likely to knock down co levels this this area but the coast guard warns accumulation can form in the rear of the boat. You don't want to be sitting sort of in the back while you're going at a low speed. Absolutely correct. We want to keep people away from the back of the boat at a low speed or when the engine is running at all. Reporter: Warnings that officials hope will prevent another case like raven's. All right, so if you're hanging out on a boat that isn't moving, you just want to make sure that engine is off. If you are on a boat that's moving at a very low speed you just don't want to hang out here in the back of the boat. That's the biggest danger and that's the biggest takeaway, George. Gio, having one of those detectors you wore would help too. That's right but you know what, on a boat like this, this is an open boat. On a boat like this it wouldn't give you such accurate readings. That boat in the back there has a cabin. An enclosed space. You are want to make sure a co detector is in that cabin and really doesn't matter if the boat is old or even new, George. Makes sense, gio, thanks very much. Never thought about all that. Makes perfect sense.
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