WASHINGTON (AP) — Tesla’s partially automated driving system steered an electric SUV into a concrete barrier on a Silicon Valley freeway because it was operating under conditions it couldn’t handle and because the driver likely was distracted by playing a game on his smartphone, the National Transportation Safety Board has found.

The board made the determination Tuesday in the fatal crash, and provided nine new recommendations to prevent partially automated vehicle crashes in the future. Among the recommendations is for tech companies to design smartphones and other electronic devices so they don’t operate if they are within a driver’s reach, unless it’s an emergency.

Chairman Robert Sumwalt said the problem of drivers distracted by smartphones will keep spreading if nothing is done.

“If we don’t get on top of it, it’s going to be a coronavirus,” he said in calling for government regulations and company policies prohibiting driver use of smartphones.

Much of the board’s frustration was directed at the National Highway Traffic Safety Administration and to Tesla, which have not acted on recommendations the NTSB passed two years ago. The NTSB investigates crashes but only has authority to make recommendations. NHTSA can enforce the advice, and manufacturers also can act on it.

But Sumwalt said if they don’t, “then we are wasting our time. Safety will not be improved. We are counting on them to do their job.”

For Tesla, the board repeated previous recommendations that it install safeguards to stop its Autopilot driving system from operating in conditions it wasn’t designed to navigate. The board also wants Tesla to design a more effective system to make sure the driver is always paying attention.