Unlike permanent restaurants or even food-service vehicles such as taco trucks, San Francisco’s small-time, mobile food vendors are simmering in a confusing legal stew.

Technically, many of the new vendors are not permitted to sell food, either by the San Francisco Department of Public Health (which enforces state codes on private property) or the San Francisco Police Department (which controls public vending) or both.

But do prohibitive regulations, such as the requirement of a hand-washing sink for employees or maintaining constant refrigeration, apply to small-time vendors? After all, they do not have employees, they operate for only short periods of time (often less than 90 minutes), and much of what they sell is nonperishable and/or is prepared in advance.

On March 8, San Francisco Supervisor Bevan Dufty sponsored a meeting to review the new trend and hear from vendors. At that meeting, Dufty promised to have some sort of progress report in May.

“I think the March meeting showed that government is willing to work with us,” said Matt Cohen, who runs SFCartProject.com. “Some of the pieces of the puzzle haven’t been figured out yet, but one of the keys is lowering the entry costs of starting a legal business.”

Cohen pointed out that there is a huge demand for street food these days, and while “informal vendors” are meeting it, they are “not going through the permitting process because it’s confusing and not designed for them.”

Lauren Bowne of Pearl’s Kitchen said that government officials were caught flat-footed by the food-cart explosion.

“The regulatory scene never anticipated this kind of thing,” said Bowne, an attorney. “The laws are old, antiquated, complicated and expensive. The way it’s set up now is illogical, so I think they’re trying to fix that.”