Transcript for How to See Warning Signs That a Balcony or Deck May Be Unsafe
"Gma" on the lookout. The safety risks of balconies after that deadly collapse in Berkeley. ABC's Jim Avila has the warning signs you should be looking out for. Reporter: Indescribable horror. It's unsafe. Reporter: Balconies, porches and backyard decks suddenly crashing to the ground. Reporter: These promgoers survive but in 2003, 12 did not. There were people covering me. Reporter: Experts say the chances of surviving a fall from even a third floor is only about 50%. A 2009 study found more than 86,000 balcony fall-related injuries over a 16-year period. It's so important to have annual inspections especially of wood terraces and wood balconies. Reporter: What to look for? Building inspector Larry bell recommends the sway test. Rock on it a little. If you're on a deck, a balcony or a terrace and you swayback and forth and that moves with you, that's a real problem. Because it indicates it's a failure of the structural connections. Reporter: On a concrete structure like this, be on the lookout for any cracks. The biggest culprit on wooden structure, rot and water damage. Rotting action is the biggest cause of balcony and terrace failures. You look at the corners of the decks and if you see little teardrops or little black marks like running of mascara, that tells you there's probably water that got into the building and now is leaking out. Go over to the guardrail and I do one of these and see if it moves. If it moves, that's not a good guardrail. Reporter: Too much weight and too many people can also be a factor. Ask your landlord how much your balcony or deck can safely hold. And then try the elbow test. If you feel claustrophobic on an outside deck there are too many people on that deck. You should have enough room around you that you're not shoulder to shoulder. You're not being pressed up against the guardrail. You shouldn't have people in your elbow space. Reporter: And finally says the inspector, perform these checks and tests before hosting every summer party. For "Good morning America," Jim Avila, ABC news, Washington.
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