The recommendations delivered to the FAA on Friday are only that: recommendations. The agency can choose to ignore them or fold them into its thinking as it writes its final rules for commercial drones. If the recommendations are adopted, they would address a key regulatory conundrum that has frustrated commercial drone advocates for years—that the most interesting uses for drones are those that solve problems for people, yet the FAA generally won’t allow drones to fly over populated areas.

The recommendations come from the Micro UAS Aviation Rulemaking Committee, or ARC, a government-sponsored committee chartered to advise the FAA on the best ways to regulate so-called “micro UAS,” or unmanned aircraft systems weighing less than 4.4 pounds. Industry advocates like the Small UAV Coalition—a lobbying coalition backed by the likes of Google (GOOG) and Amazon (AMZN)—have long argued that small quad-rotor drones don’t pose the same kind of public safety threat as their larger counterparts and shouldn’t be regulated the same way (currently the FAA defines any drone up to 55 pounds as a “small drone”). ARC’s recommendations reflect that idea, breaking the smallest drones down into four categories that would be cleared to fly around people under varying circumstances.

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Drones in the first category would weigh no more than a half-pound and could fly unrestricted just about anywhere, including over crowds of people. The burden would fall to commercial drone manufacturers to demonstrate that aircraft in this category that hit someone would have no greater than a 1% chance of causing serious injury at full speed.

The other three categories would require drones to fly at least 20 feet over the top of the crowd and maintain 10 feet of lateral space between the aircraft and people. One such category would largely be made up of small quad-rotor weighing four or five pounds, and manufacturers would again have to meet the less-than-one-percent chance of serious injury threshold. Flights over crowds would depend on the design and the ability to demonstrate safety, but the larger idea is that regulators would take a more active oversight role in this category of somewhat larger aircraft.

A third category would place a lower safety threshold on drones aimed at specific commercial uses in a predefined area—a construction job site or around wind turbines or cell towers that need inspecting, for instance. In this instance, the risk of serious injury from a malfunctioning drone would have to be 30% or less. In this case, the people on the ground would be made aware of the drone operations beforehand and flights overhead would be short in duration rather than sustained.

The final category of drones could maintain sustained flights over crowds and would only have to meet the less stringent 30% safety standard. But operators and manufacturers would have to work more closely with the FAA and local authorities to demonstrate how risks to the crowd could be managed in case of trouble.

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The FAA defines “micro” drones as those weighing less than 4.4 pounds, but the Micro UAV Aviation Rulemaking Committee did not set weight ceilings for the latter three categories. If the FAA decides to adopt some or all of the recommendations, larger drones—the kind that would be necessary delivering packages, for example—could be allowed to fly in populated areas if they can meet the proper safety standards.

Exactly how drone manufacturers will demonstrate the safety of their drones remains an open question, and one the FAA won’t have to answer before releasing comprehensive rules for small commercial drones later this year. Efforts to regulate micro drones differently than other small drones are part of a separate initiative, FAA representatives have said, and there’s currently no public deadline for when the FAA will make a decision on the recommendations.