WINSTON-SALEM, NC -- When someone's heart stops the clock starts ticking. More than 350,000 people go into cardiac arrest outside of the hospital each year. Only 12% of them survive. Less than half of those people are given CPR. If someone starts hands-only CPR when that clock starts ticking, the victim's chance of survival triples.

Health experts say people underestimate how effective and important hands-only CPR is, meaning chest compressions. When you see someone have a medical emergency, do "The Three C's."

1. Check: See if they are responsive. See if breathing is normal.

2. Call: Call 911.

3. Compress: Start chest compressions. Click this link for an example of what to do. Don't stop doing CPR until help arrives.