WASHINGTON — The government is readying rules largely favorable to companies that want to use small drones for commercial purposes, according to a federal analysis, potentially leading to the widespread flights by unmanned aircraft performing aerial photography, crop monitoring, inspections of cell towers and bridges and other work.

An economic analysis by Federal Aviation Administration, which was inadvertently posted online, describes draft rules submitted by the agency in October to the White House budget office to review. The rules, in the works for years, are expected to be released at any time.

The regulations would apply to drones weighing less than 55 pounds. They would improve safety by using small, lightweight unmanned aircraft instead of heavier, manned aircraft that “pose a higher level of risk,” the analysis said. It notes that between 2004 and 2012, there were 95 fatalities involving climbers working on cell and other towers.

If the rules would prevent only one fatality by using a small drone instead of a tower climber, the $9.2 million saved — the amount the government says is the economic value of a single life — would exceed the entire cost of the regulations to society, according to the document.

The analysis does not offer a total estimate on the annual economic benefit of regulations, but says it would exceed $100 million a year. For example, about 45,000 annual bridge inspections could be conducted with a small drone. Most bridge inspections currently employ hydraulic mobile cranes called “snoopers.” The average cost of an inspection using a snooper is $3,250. Cable bridge inspections are even more expensive because they often require a 200-foot aerial lift.

The FAA currently bans all commercial drone flights except for those by a small number of companies that have been granted waivers. Congress has been leaning on the FAA to move faster on regulations that would allow a wide variety of companies to employ drones for everything from monitoring pipelines to delivering pizzas. The FAA was to issue final regulations by September 2015, but that appears unlikely.

The document indicates the agency has dropped its insistence that drone operators have the same licenses and medical certificates required for pilots of manned aircraft. Industry officials complained that obtaining a private pilot license or medical certificate would be unnecessarily burdensome.