Sameer Yousef, a lead cabin cleaner for ABM, one of the companies hired by airlines, oversees a team of four that cleans United airplanes at San Francisco International Airport. On average, he said, his team cleans everything from the galley, floor, lavatories, seats and windows on more than a dozen airplanes every workday. “To clean, we need 10 to 15 minutes, but they give us seven or six,” or even less time for quick turns, he said. “It’s a very big pressure for us. They don’t give us more people to help.”

Mr. Yousef said the job is hard. “We have problems with our backs. All day, you’re bent doing seat pockets, doing the seatbelts. You go down and look under the seats and go up, jumping in the overhead.”

Cabin cleaners are also responsible for conducting periodic security sweeps in the airplanes, but Mr. Yousef said that he and his team are not given flashlights or mirrors for the task. He uses the flashlight on his own mobile phone.

A report in 2015 by the Government Accountability Office detailed the “limited time” cleaners have before passengers for the next flight begin boarding, and noted that cleaners might need to request more time for “additional cleaning necessary to decontaminate the aircraft.” Cleaners told the G.A.O. that “after incidents when a traveler became ill during a flight, the cabin crew does not always notify them of potentially infectious bodily fluids that had contaminated the aircraft.” The report concluded that the United States lacks “a comprehensive national aviation-preparedness plan aimed at preventing and containing the spread of diseases through air travel.”

Michael Ostendorf, a senior vice president for aviation operations at ABM, said that the company cleans a variety of airplanes for United, American, Delta, Southwest and other airlines and that a typical turn time should be 10 to 15 minutes.

“Now, during an operation that could change, it could get better, or it could get worse depending on the airline’s on-time performance for that day,” he said. Both overnight and deep cleans are more extensive in terms of the time and crew allocated. He said federal rules prohibited him from discussing the equipment ABM provides to cabin cleaners for security sweeps.

Robert W. Mann Jr., an aviation consultant based in Port Washington, N.Y., said that a clean or dirty cabin is the first thing passengers take note of and that it colors their entire experience. “When customers perceive cleanliness problems they conflate that with a perception that an airline might not be maintaining its airplanes, which is not a good thing,” Mr. Mann said. But he noted that modern cabin designs are easier to clean because they don’t have as many “grooves and recesses that tend to just collect dirt.”