How are plastics identified for recycling by number codes and abbreviations?

To facilitate recycling, most plastics used in consumer packaging—such as bottles, food trays, and cups—are marked with an identification system. This system consists of a number enclosed within a triangle, accompanied by an abbreviation that identifies the specific type of polymer used in the product.1

This labeling is essential because thermoplastics must be sorted by type before they can be effectively remelted and processed into new materials. Without proper segregation, mixing different polymer types or contaminants can result in a material that is unsuitable for high-quality applications.23

Common examples of these identified materials include:
* PET (or PETE): Polyethylene terephthalate, frequently used for beverage bottles.13
* HDPE: High-density polyethylene, often found in containers like milk jugs.14
* PVC: Polyvinyl chloride, used in various rigid applications.34

While these codes help streamline the sorting process, it is important to note that less than 10 percent of all plastic products are recycled after their first use, as many plastics are utilized in long-term applications where recovery is difficult.1