If you’ve taken up recycling, you’re already helping to make the world a greener place. But there are some essential tricks of the trade. A very common concern in the recycling realm is knowing how clean recyclables must be before you throw them in the bin.

Contaminants can ruin certain recycling processes, but do you really have to rinse all the sour cream out of the container before recycling? Is it different for each type of recyclable?

While guidelines vary by location, here’s a basic guide to help you determine the standard of cleanliness for your recyclables:

Rinse Jars, Bottles and Cans

As a general rule, for things like bottles and jars, a quick rinse is more than adequate. You don’t need to scrub the remains in the mayonnaise jar with soap before recycling, and a few spots won’t likely hinder the process.

For most items, just fill the container with water and vigorously swish the water around inside. (Or better yet, use leftover dishwashing water just before you drain it.) If the residue is sticky like jelly or honey, you may need to use a scrub brush or scraper to remove more of the product.

Cardboard and Paper Guidelines

Note that grease and oil make cardboard and paper unrecyclable, so pizza boxes covered in grease aren’t fit for the recycling bin. However, if the box is mostly clean with just a few specks of grease, you’re fine to recycle it.

The same goes for other contaminants. If you’re making pancakes and a drop of egg lands on the box, it’s still clean enough to…