The Significance of Numbers on Plastic Recycling
- In 1988, The Society of the Plastics Industries, Inc. (SPI) introduced a method of categorizing plastics called a resin identification coding system. Simply put, the number you see on the bottom of a plastic container indicates the type of plastic.
- These nationally recognized codes help facilitate the recycling process:
1 = PET (Polyethylene terephthalate)
2 = HDPE (High-density polyethylene)
3 = Vinyl
4 = LDPE (Low-density polyethylene)
5 = PP (Polypropylene)
6 = PS (Polystyrene)
7 = Other - Type 2 plastics are easy to identify.Image by Flickr.com, courtesy of Mark Kobayashi-Hillary
It should not take you long to remember that a milk jug always goes into the "Type 2" recycling bin, and that most soda bottles are stamped with a "1." - Just because that plastic take-out container has a number stamp does not necessarily mean you can throw it in the recycling bin. Ask your local recycling center or organization for a list of plastic types they will collect.
- Not all plastics have numbers stamped on them. According to The Society of the Plastics Industry, as of January 2010 only 39 states have laws stipulating the use of SPI codes on "bottles and rigid containers."
Look Out for Number 1 (or 2 or 3)
SPI Resin Identification Codes
Know Your Numbers
Ask First
Missing Numbers
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