Restaurants, hotels and other businesses that sell takeout food in Minneapolis have six weeks to go before they'll no longer be able to package up your food in foam containers — or in any container that isn't recyclable, reusable or compostable.

The Minneapolis City Council voted last year to tighten up an earlier ordinance by outlining which products can and can't be used and making it a required check for health inspectors, who will be able to issue warnings and citations for businesses that don't comply with the rules. Now, the city and industry associations are trying to make sure businesses understand the changes and are ready for April 22 — Earth Day — when the ordinance goes into effect.

Business owners will get a chance Thursday to learn more about the rules and check out a variety of environmentally friendly options at a Packaging Fair hosted by the city and a handful of other groups. Daniel Huff, the city's environmental health director, said the goal is to give people a chance to figure out if their containers are still allowed and do some comparison shopping from vendors who can provide other options.

The ordinance outlaws two types of polystyrene containers and more rigid plastic containers that are marked with a "6" inside the recycling symbol. But sorting out what's in and what's out can be confusing: some paper cups, for example, which appear to meet recycling or composting standards actually don't because they are lined with plastic.

Huff said the city's ordinance does provide for some exceptions. Utensils and straws aren't covered by the new rules, and businesses will get a temporary break on lids for hot-beverage cups and plastic-lined paper products. The cups will be banned in 2017, around the time compost pickup will be available citywide.

Businesses can also apply for individual variances to the ordinance. Those that follow all the rules, however, will be able to market themselves with the city's new "Green to Go" logo, indicating that they exclusively use environmentally friendly containers.

Dan McElroy, president and CEO of Hospitality Minnesota, said most of his members are amenable to the changes. While some recyclable or compostable packaging can be more expensive than other options, he said the exemptions provided by the ordinance helped erase some fears of soaring costs.

Thursday's event will be held from 9 a.m. to noon at the Lake Calhoun Event Center.