Emily Gardner, 14, from Gloucester, drowned when an ill-fitting buoyancy aid snagged on a speedboat which capsized in Brixham, Devon in May 2015.
Parents Clive and Debbie Gardner set up Emily's Code to highlight safety issues for small boat owners and users.
They said something as simple as checking a buoyancy aid or lifejacket fits properly could save a life.
Emily was with two friends and her best friend's father, Paul Pritchard, on a 16ft (4.8m) speedboat when a wave hit the vessel, causing it to overturn.
An inquest into Emily's death heard all four were thrown into the water. Emily was trapped underneath the boat after one of the straps on her buoyancy aid caught on a cleat.
Mr and Mrs Gardner said: "Many parents like us have no awareness of recreational boating safety guidelines and have never used a boat before.
"When Emily went on a day trip with her friends we were reassured that safety was paramount and that the equipment was top notch.
"If just one family sees this and takes action to protect their children on the water, then Emily's Code will have succeeded and Emily's name will live on."
The code has the backing of the Royal Yachting Association, HM Coastguard, British Water Ski and Wakeboard, and the RNLI.
Emily's Code:
The family of a teenage girl who drowned on a sailing trip have launched a safety code in her memory.