Recycle this page when done

You're probably familiar with the chasing arrows symbolic of recycling.  In fact, you may think they're chasing you!  They seem to appear out of nowhere to remind you that you didn't sort your garbage.  (And who designed that thing anyway?  Doesn't it look like some sort of impossible figure that M.C. Escher would've dreamed up?)

Okay, there's no need to be paranoid -- they're not after you.  Actually, when it comes to the containers they're printed on, they're supposed to be as inconspicuous as possible.


The symbol code we're familiar with was designed by The Society of the Plastics Industry (SPI) in 1988 to allow recyclers to differentiate different types of plastics and to provide a uniform convention that manufacturers could implement nationwide.  Since recyclers target post-consumer plastics, the SPI code is most commonly found on household packaging materials.

The Rules of Use

SPI and the Federal Trade Commission (FTC) have established guidelines for use of the code:

I'm not a lawyer nor did I ever claim to be.  So if you're a manufacturer please consult SPI for a complete description of guidelines.

What's What

Now for the reason you came to this page!  Below you'll find the SPI symbol and the polymer that it represents along with a quickie description of uses for that polymer.  To learn everything you ever wanted to know about the polymers in question, just click on the name.

Poly(ethylene terephthalate):  Soda bottles, water bottles, vinegar bottles, medicine containers, backing for photography film.

So why PETE and not the more logical PET? Turns out a company making condensed milk already had a trademark of the abbreviation "PET" so it couldn't be used for recycle numbers. OOPS!

High-density Polyethylene:  Containers for:  laundry/dish detergent, fabric softeners, bleach, milk, shampoo, conditioner, motor oil. Newer bullet proof vests, various toys.

Poly(vinyl cloride):  Pipes, shower curtains, meat wraps, cooking oil bottles, baby bottle nipples, shrink wrap, clear medical tubing, vinyl dashboards and seat covers, coffee containers.

Low-density Polyethylene:  Wrapping films, grocery bags, sandwich bags.

Polypropylene:  Tupperware®, syrup bottles, yogurt tubs, diapers, outdoor carpet.

Polystyrene:  Coffee cups, disposable cutlery and cups (clear and colored), bakery shells, meat trays, "cheap" hubcaps, packing peanuts, styrofoam insulation.

The hotdog of plastics!  Products labeled as "other" are made of any combination of 1-6 or another, less commonly used plastic.

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