NASA will probe the workplace culture at SpaceX and Boeing, including drug use, just months before both companies are scheduled to launch astronauts on their first test flights, the agency confirmed Wednesday.

The “cultural assessment study” will be conducted over the next few months and comes as both companies are preparing for a busy 2019. SpaceX’s Crew Dragon and Boeing’s Starliner are both scheduled to launch test flights next year.

“We fully expect our commercial partners to meet all workplace safety requirements in the execution of our missions and the services they provide the American people,” said the agency in a statement.

SpaceX and Boeing became NASA’s commercial partners in 2014 and signed agreements to develop systems to launch astronauts to the International Space Station from American soil.

After the space shuttle program ended in 2011, NASA has been purchasing seats for its astronauts on board Russia’s Soyuz at $81 million apiece until SpaceX and Boeing are ready to begin taking astronauts into space.

The Washington Post reported Wednesday that the probe was prompted by SpaceX chief executive officer Elon Musk’s marijuana smoking during a live podcast in September. The podcast was broadcast from California, where marijuana is legal — though it remains forbidden at the federal level.

A NASA spokesperson declined to comment on whether Musk lighting up was what prompted the review. A SpaceX representative did not immediately respond to questions about the timing of the review and what may have been the catalyst.

The timing and the public statements about the review are unusual, especially since both companies are set to launch astronauts next year, said Jim Cantrell, CEO at Vector Space Systems and a founding member of SpaceX.

Cantrell said he doesn’t “ever remember anything like this happening” throughout his decades of experience, but suggested it may be a way for NASA to deal with any “internal strife” generated by the headlines of Musk’s marijuana smoking.

“SpaceX actively promotes workplace safety and we are confident that our comprehensive drug-free workforce and workplace programs exceed all applicable contractual requirements,” Musk's company said in a statement.

Boeing's culture “ensures the integrity, safety and quality of our products, our people and their work environment” the aerospace company said in a statement Wednesday.

Boeing's Starliner is set for two test flights later next year, with the second flight carrying astronauts.

SpaceX is scheduled to launch its Crew Dragon in January. A test flight in June will carry humans into space, marking a major milestone for Musk and his team. The team is gearing up for a new era of commercial space flight. In 2023, SpaceX plans to take the first tourist to the moon.