How to Properly Recycle

Have you ever heard the phrase ‘When in doubt, recycle it!’ This practice is called ‘wishful recycling’ and it is actually incredibly harmful for the environment and your local material recovery facility (MRF). Wishful recycling can actually contaminate recycling streams and is causing tons of recycling to be sent to the landfill. In order to understand why this is harmful and how to recycle correctly, we need to understand what actually happens to the items we place in our blue bins.

How Recycling Works

Recycling laws are different and recycling in general will look different everywhere in the world. Below is a diagram outlining commonly how single stream recycling works in the US. The diagram is from Charles County, MD, and actually matches what happens to our single stream recycling at UMBC.

The material recovery facility (MRF) at step 3 of the recycling process, sorts the material and sells it to be reprocessed. They decide what can and cannot be recycled based on what materials they can sell to buyers. Buyers are looking for clean bales with very little contamination (i.e. materials they cannot easily reprocessed and sold).

Recently, recycling markets have fallen due to high contamination levels in the single stream recycling coming from the US and European countries. In response, material recovery facilities have been cracking down on contamination and what items they will accept. If a truck load of recyclables comes to a MRF and it is highly contaminated, the whole load could be sent to the landfill.

How to Recycle Correctly

Check with Your Local Municipality

Your local municipality most likely has a contract with the waste hauler and MRF. Those entities will work with the local government to disseminate recycling information. The information usually lives on your local government’s Department of Public Works website.

Do NOT Place Plastic Bags in Single-Stream 

No matter where you live in the US you should NEVER place a plastic bag into a single stream recycling bin. This includes grocery bags, bubble wrap, flexible plastic packaging, saran wrap, and zip lock bags. These items get caught in the machinery used at MRF’s and can cause breakdowns and even worker injuries.

Other Items that Should Not be Placed in Your Recycling Bin

This a full list of common items that cannot be recycled anywhere. Items in green can be composted at the Commons on campus.


  • Paper Towels
  • Paper Plates
  • Tissues
  • Paper Cups
  • Receipts


  • Greasy Pizza Box
  • Juice and Milk Cartons
  • Pringles Cans

Plastic (even with recycling symbol):

  • Solo Cups
  • Plastic Bags and Films (find out the location of the TREX plastic film recycling bins on campus)
  • Chip Bags
  • Styrofoam
  • Plastic Utensils
  • Plastic Straws

*Recycling rules vary, so again check with your local municipality

What are Plastic Identification Codes?

Have you ever wondered what the number with the recycling symbol on plastics is for? That symbol is the Plastic Identification Code of a product, and identifies the type of plastic resin a product is made of. The code was created, so reprocessing facilities could easily separate resins and locate which items could be recycled again. It is important to note that this code does not automatically mean something is recyclable. Often times municipalities only accept plastics #1, #2, or #5 (less common). Check your local recycling laws to see what type of plastics are accepted in your area.

If you have any questions about recycling on campus please contact us at & take our Waste 101 Quiz to test your sorting knowledge!