A drone-delivery company that has made thousands of medical drops in Africa, including distributions of Covid-19 vaccines, was approved by US regulators to operate as a small air carrier.

Zipline International Inc., which already is making deliveries with companies such as Walmart Inc., said Tuesday that the Federal Aviation Administration certification would allow it to expand by shipping heath-care products from its North Carolina headquarters.

“We are one step closer to making safe, clean and quiet instant delivery a reality for communities across the US,” said Keller Rinaudo, chief executive officer at Zipline.

Several companies, including Alphabet Inc.’s Wing LLC, Amazon.com Inc.’s Prime Air and United Parcel Service Inc.’s UPS Flight Forward, have received similar approvals, according to FAA’s website. While they and other companies are testing delivery systems, the FAA hasn’t written basic regulations and safety standards to allow for routine product drops by drones. Zipline’s approval as an air carrier occurred on Friday, the company said.

Unlike most of its competitors that operate drones that can take off vertically, Zipline uses an aircraft that flies more like a traditional plane and is capable of traveling longer distances. The company says it has made more than 300,000 commercial deliveries, many of them medical supply drops in Africa.

It is also seeking approval for a type of automated drone air-traffic system to ensure its aircraft steer clear of other planes and helicopters, Rinaudo said. It uses an array of microphones that can detect the sounds of other aircraft, even in clouds, he said.