The FAA released a new study Friday to help determine how dangerous it really is to get hit with a drone falling out of the sky.
While the idea of having a drone fall on your head isn’t pleasant, it turns out you’re much more likely to suffer an injury from getting hit by a block of wood or a hunk of metal than a flying robot of the same size, according to the new report.
That’s because the shape of a typical four-propeller consumer drone causes it to fall more slowly than a block of wood. Drones are also more likely to deform in some way during a collision and absorb more of the energy from the impact, the researchers found. The report was written with the help of a consortium of universities, led by the University of Alabama in Huntsville.
DJI’s Phantom 3 drone, for example, was found to have about a .03 percent chance of causing a head injury if it fell on a person, compared to a block of wood of the same mass, which was found to have a 99 percent chance of a head injury. But while your head may not be injured by a falling drone, the chances of suffering a neck injury if hit by a Phantom 3 drone increased to around 13 percent.
The report also found that blade guards used to protect the rotors help to decrease the severity of an injury from collisions and should be required for safe flight over people.
These findings could impact the outcome of new rules on flying drones, which are still being written in many countries around the world, including the United States. The Federal Aviation Administration is expected to continue to seek input from the public and industry experts on how drones should be allowed to fly over people, beyond line of sight of the operator and at night.
The current threshold for determining if a drone needs to be registered with the FAA — unmanned aircraft weighing more than 250 grams — was decided in part using Cold War-era military projections on the lethality of being hit with debris in a nuclear fallout, as Recode reported last month.
The FAA will begin a new phase of research on drone safety in June, the results of which will be used to develop tests for drone manufacturers to certify their aircraft for safe flying over people.
This article originally appeared on Recode.net.