Before a standardized system of recognizing plastic resins was established, plastic manufacturers and recycling firms alike, had their hands full when determining which forms of plastic packaging were acceptable, both prior to use, as well as after. Back in the 80’s for instance, one company may have been perfectly content mixing all plastic materials together during the recycling process, while another may have required that plastics be sorted by type and categorized according to their respective properties post consumer use. Especially when dealing with companies across state lines, or even worse, country borders, one can only imagine the varying degrees of categorization employed by plastic companies not having standard of protocols for categorizing plastics, as well as the unnecessary headaches when sorting methods proved counterproductive.
A Recycling Numbers System is Established
To facilitate the complex nature of plastics and the growing need to standardize plastic resin identification in the plastics industry, the Society of the Plastics Industry, Inc., established an identification coding system that identifies each plastic’s resin code, description, property, product application, and whether or not the plastic was made with recycled content.
Established in 1988, the plastic resin identification codes, also known as recycling numbers, were introduced to meet recycling standards while at the same time, providing plastic manufacturers with a reliable, uniform system that could be applied on a national level, across company lines. At the time, recycling firms, driven mostly by state mandates in an attempt to cut down on pollution, were the major employers of this code. Today, plastic manufacturers and recycling firms employ this system, not only to identify which types of plastic are recyclable, but even more so, to provide plastic manufacturers with a clear and consistent way to identify key plastic resins and symbols across state lines.
Updates to the SPI Plastic Resin Identification Codes
With revisions to the original 1988 version not recommended until 8 years post the new millennium, the coding system seemed to be working quite well for the 6 major plastic resin categories not including the 7th “other”: polyethylene terephthalate (PETE); high density polyethylene (HDPE); polyvinyl chloride (PVC or vinyl); low density polyethylene (LDPE); polypropylene (PP); or polystyrene (PS).
In 2008, the Society of Plastics Industry(SPI) teamed up with ASTM International, a leading international consensus organization, in an effort to begin work on expanding the current resin identification code system. In 2010, the company issued ASTM D7611-Standard Practice for Coding Plastic Manufactured Articles for Resin Identification, with further revisions made in 2013. Modifications to the original coding system include graphic symbolism used to identify plastic resin types in the form of equilateral triangles, as seen in the identification of most plastic resins available today, and are currently compliant in 39 states.
Although further revisions to the current plastic resin identification code system will still be handled by the two organizations that founded them, SPI and ASTM, the Federal Trade Commission and State Attorney General claim that the code’s revisions and newly sanctioned guidelines for proper plastic resin codes usage should be just enough to keep plastic manufacturing companies informed uniformly, and recycling firms honest from making misleading environmental claims.