• Zoox's exemption to rules requiring human controls comes with added reporting requirements

• Company allowed to deploy 2,500 vehicles annually for two years

• NHTSA aiming for new autonomous vehicle safety standards by end of Trump administration

SAN DIEGO, July 30 (Reuters) - Amazon's, opens new tab Zoox unit won ​U.S. approval on Wednesday for limited commercial deployment of its novel steering-wheel-free robotaxis, a first for the autonomous ride industry, ‌the U.S. auto safety agency said Thursday.

The exemption from National Highway Traffic Safety Administration rules requiring human controls, first reported by Reuters, marks a milestone for companies developing robotaxis from the ground up, rather than modifying conventional cars under safety regulations written long before self-driving technology emerged.

The Reuters Daily Briefing newsletter provides all the news you need to start your day. Sign up here.

Along with Zoox, whose electric carriage-style vehicle has two rows of inward-facing ​seats and a top speed of 75 miles per hour, others such as Tesla , opens new tab and Alphabet's , opens new tab Waymo are racing to expand autonomous ​ride-hailing services in the United States.

NHTSA Administrator Jonathan Morrison told Reuters that Zoox had received clearance to commercially deploy up to 2,500 vehicles in each of the next two years.

ADDITIONAL REPORTING REQUIREMENTS

The agency said it determined the vehicle is as safe as an ​equivalent vehicle meeting federal motor vehicle safety standards that are being waived. Zoox cannot sell any of the vehicles to the public.

"We can say pretty ​clearly that the systems in place on the Zoox exceed the equivalent performance requirements of a compliant vehicle," he said in an interview. "But we still want to make sure that the automated driving system will operate appropriately."

As part of the exemption, NHTSA is placing additional reporting requirements on Zoox for issues such as crashes or stopping inappropriately on ​roads, and the regulator will adjust the conditions based on how the vehicles behave.

"We have the ability to pull the exemption if we see ​major safety issues," Morrison said.

All remote operators must be located in the United States, NHTSA said. Zoox must publish maps of areas indicating where the vehicles are operating.

Zoox ‌currently carries passengers in parts of Las Vegas and San Francisco as part of testing. The exemption would allow Zoox to charge them fees, subject to state and local approvals.

Morrison said NHTSA expects to develop the first federal safety standards for automated driving systems by the end of the Trump administration. It is also proposing to overhaul some existing rules written with human drivers in mind such as requiring brake pedals and rear-view mirrors.

SAFETY CONCERNS

Zoox's approval caps ​its years-long effort to commercialise its robotaxi ​under regulations developed before self-driving technology emerged.

Tesla has started producing a Cybercab that lacks human controls, but it has not outlined its path for regulatory approvals.

Regulators are trying to change rules to allow more self-driving technology while maintaining safety.

This month, Morrison issued a ​strongly worded letter telling autonomous vehicle (AV) developers to "immediately focus" on fixing what NHTSA identified as "a clear pattern ​of driverless AVs interfering with law enforcement and other first responders."

That, along with issues such as robotaxis driving around stopped school buses or into construction zones, freezing on water-flooded roads or busy intersections and breaking traffic laws, has raised public concerns around safety and led to recalls.

"If we continue seeing issues, we will not hesitate to use the full ​extent of our enforcement authority," Morrison said.

Following the letter, Zoox recalled its fleet of 105 autonomous ​vehicles to update the software, saying they might not detect heavy smoke, particularly in active emergencies.

Morrison will speak on Thursday about some of the agency's safety efforts at SAE International's Automated ​Transportation Symposium in San Diego.