Erin Wade, the owner of 10-year-old Oakland mac-and-cheese restaurant Homeroom, is expanding her restaurant’s widely praised internal system for dealing with sexual harassment from customers. Wade shared that system, which she now calls the Color Code of Conduct, in a widely-read Washington Post op-ed article last year. Since then, it’s been named a national best practice by the Equal Employment Opportunity Commission (EEOC) and spread to bars and restaurants across the country.

Now, Wade has adapted the Color Code of Conduct to an eye-catching restaurant safety poster and illustrated zine called Not on the Menu. While they’re not a cure-all for bad actors in the restaurant business, they’re simple ways for more restaurants to get onboard with a proven system — and with one in ten Americans working in the restaurant industry, Not on the Menu stands to make a major difference.

After Wade’s article, “there was just an outpouring of enthusiasm and support that was really overwhelming,” she recalls. The #metoo movement had hit the restaurant industry, and Ken Friedman, Mario Batali, and other prominent figures had been credibly accused of sexual harassment. “People were so desperate — we still are — for a solution, because we spent a lot of time identifying the problem,” Wade says. In this case, that problem is bad customers, not bad bosses. “We’ve been using this for years, and it’s effective,” says Wade.

As Not on the Menu’s poster explains (with illustrated produce), the Color Code of Conduct has three levels for servers to report to managers: Yellow for a creepy vibe from a customer; orange for a comment with sexual undertones; and red for overt sexual comments, touching, or repeated orange level behavior.

Each color calls for action. Red is immediate expulsion from the restaurant. Orange means a shift manager takes over the table. And yellow means a manager must take over the table if a staff member wants them to.

What’s effective about the system, Wade explains, is that it’s quick, it doesn’t require the server to relive or justify the gravity of the offending behavior to a manager, and it comes with an automatic response, no questions asked. Another reason for its efficacy, Wade suggests, is that most harassers start out at yellow, testing the waters before escalating their behavior. The system also takes women servers at their word, paying attention to the “canny sixth sense [women have] for unwanted attention,” as Wade wrote in her op-ed.

“Over the last three years, Homeroom has served over a million mac and cheeses with only a handful of code reds on the restaurant floor during that time,” the Not on the Menu website claims. And these days, Homeroom is far from alone in the effort. Hundreds of other restaurants and bars in the Bay Area and beyond have implemented the system, from State Bird Provisions in San Francisco to Existing Conditions in New York City.

Not everyone needs a visual aid to explain the Color Code of Conduct — but it could help the system spread. “We just wanted to make it easy,” says Wade. “This is intended to be used by restaurants [placed alongside] those stupid posters that no one reads,” like labor law or choking first-aid signs, “but made my a rad woman artist, and readable to a normal human, not a lawyer.”

Wade, for the record, is herself a former lawyer, and that rad artist is the LA-based illustrator Ellen Surrey. Some businesses had also requested a training manual for the system, with a script of set examples. They produced that part as a zine.

After her Washington Post op-ed, Wade was approached by a number of consultants interested in formalizing her system. Many of them were men, and that rubbed her the wrong way, she says. “[The system] was developed by women at a very feminist company, and it was going to be monetized by men.”

Wade hesitated “to make this into something that could make money.” But if someone was going to profit from it, it was going to be women. A portion of proceeds from sales of not on the Menu posters ($10 for 11” x 17” or $20 for 24” by 36” and laminated) and zines ($10) will go to SF-based La Cocina, which supports women food entrepreneurs.

That will help, too, says Wade. “Ultimately this is solved with more female leadership in the food space.”