Plastic Resin Codes

The Society of the Plastics Industry, Inc. (SPI) introduced its plastic resin identification coding system in 1988.

The SPI code was developed to meet recyclers’ needs while providing manufacturers a consistent, uniform system that could apply nationwide. Because municipal recycling programs traditionally target packaging - primarily containers - the SPI coding system offers a means of identifying the resin content of bottles and containers commonly found in the residential waste stream.

A recyclable plastic container using this scheme is marked with a triangle of three "chasing arrows", which encloses a number giving the plastic type:

1. PET (PETE): Polyethylene Terephthalate - Commonly found on: 2-liter soft drink bottles, cooking oil bottles, peanut butter jars.
2. HDPE: High Density Polyethylene - Commonly found on: detergent bottles, milk jugs.
3. PVC: Polyvinyl Chloride - Commonly found on: plastic pipes, outdoor furniture, shrink-wrap, water bottles, salad dressing and liquid detergent containers.
4. LDPE: Low Density Polyethylene - Commonly found on: dry-cleaning bags, produce bags, trash can liners, food storage containers.
5. PP: Polypropylene - Commonly found on: bottle caps, drinking straws
6. PS: Polystyrene - Commonly found on: "Styrofoam peanuts," cups, plastic tableware, meat trays, take-away food clamshell containers
7. OTHER: Other - This plastic category, as its name of "other" implies, is any plastic other than the named #1 – #6, Commonly found on: certain kinds of food containers, Tupperware, and Nalgene bottles.

Click here for more detailed information, including the "chasing arrows" graphic.