Transcript for 3 killed in boiler explosion caught on camera
We are back now with an alert about boilers after that deadly explosion in St. Louis that was caught on surveillance camera and ABC's Linzie Janis is at the pse & G training facility in New Jersey. Good morning. Reporter: Good morning. In St. Louis that industrial boiler exploded with deadly consequences but a reminder more than 10 million homes across America have boilers and more than 100 million have water heaters. Both can explode if the pressure inside builds too high. This is the moment a piece of equipment found in many homes and buildings explodes. Watch again as part of an industrial boiler inside a St. Louis plant launches like a rocket into the air. It was a little chaotic. People didn't know where to go or what to do. Reporter: This morning, three are dead and several others are seriously injured after part of the heating system the size of a van and weighing more than a ton flew roughly 500 feet before crashing through the roof of another building nearby. Other pieces of debris several feet long damaging additional buildings in the area. This pipe even flying across the street like a javelin into this man's truck. We heard something blow up. I opened the tore and seen dust flying and stuff flying everywhere. Reporter: This isn't the first time a boiler accident has been caught on tape. In 2015, one exploded in a home in Washington state. Spraying nails and hot steam across a children's playroom. It's just like a pressure cooker. It's not very common. But with lack of maintenance and proper repairs, it can happen. Reporter: Experts say explosions like this could happen if there's too much pressure built up inside the tank in both boilers and water heaters. Something seen on the discovery channel's show "Mythbusters." As for the blast in St. Louis, investigators are now looking into the cause. Ear's going to be looking at all the records and make sure that everything was up to date. Reporter: Experts say this is a warning for us all. Whatever you use to heat your home whether it's a furnace, a boiler, even water heaters they should be looked at, inspected by a professional once a year. If you do have an older home and a boiler like this one there are a couple of things you can do once a month to look at it. Make sure it's working properly. This is the water gauge. You want to make sure that's about halfway up. If it's too high or too low call somebody out. If we can come around the side here, this is what is known as the blowoff pipe where the boiler releases pressure. You want to make sure that area near the bottom is unobstructed and if you see it leaking water, call somebody right away. Michael. And, Linzie, anything else we can do to make sure our families are safe. Experts say both furnaces and boilers are leak carbon monoxide if they're not properly maintained so make sure you have detectors in your home. Michael. Thank you, Linzie. Great advice. When we come back you have
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