Posted by Jeff Knapp on Mon, Apr 12, 2010
In 1988 The Society of Plastics Industry (SPI) developed the Resin Identification Code (RIC) system. The codes were developed to provide a consistent national system to help workers on sorting lines identify post-consumer bottles using the 6 basic packaging resin classes. The RIC system was not intended to imply recyclability. Soon after their introduction, 39 states mandated that bottles and containers be marked with the recycling plastic Codes to assist source segregation at households. This practice introduced the general public to the existence of the Code. States also insisted on having an "OTHER" category. The publics misinterpretation of the Codes, particularly OTHER, has become a serious problem. The 6 basic resin classes (recycling numbers) no longer suffice to meet the needs of recyclers, particularly with regard to new resins and multi-material construction. In 2008, SPI asked ASTM to take ownership of the codes. ASTM agreed and initiated work to convert from the RIC to the ASTM standard format and address various issues using the ASTM consensus's based process. ASTM is composed of 32,000 volunteer members from over 125 countries: consumers, producers design professionals, researchers, and academia. Anyone with interest can participate on the ASTM committees.
ASTM's main focus
- What to do about "7"
- What to do about the Chasing Arrows symbol?
- What defines "1", "2", "3", etc?
- How do we handle multi-material and multi-layer structures?
- Are new codes needed
Some information supplied from astm.org
Posted by Doug Malawey on Mon, Mar 22, 2010
Number 4 Plastics
LDPE (low density polyethylene)
Found in: Squeezable bottles; plastic soft drink, water, sports drink, beer, mouthwash, catsup and salad dressing bottles; plastic peanut butter, pickle, jelly and jam jars; oven able film and oven able prepared food trays, bread, frozen food, dry cleaning and shopping bags; tote bags; clothing; furniture; carpet. Also used in film applications due to its toughness, flexibility and relative transparency, making it popular for use in applications where heat sealing is necessary, like bread bags, dry cleaning, or frozen food bags.
Recycling: LDPE is a flexible plastic with many applications. Historically it has not been accepted through most American curbside recycling programs, but more and more communities are starting to accept it. Plastic shopping bags can be returned to many stores for recycling.
Recycled into: Trash can liners and cans, compost bins, shipping envelopes, paneling, lumber, landscaping ties, floor tile
LDPE can also be foamed or expanded. In this case it can look like EPS, (expandable polystyrene) or "Styrofoam" packaging. This is why when recycling, it's important to recognize the recycling symbol to know which plastic material you have. In the world of plastics recycling, mixing these materials can be considered contamination to a recycler.
Additional numbers coming soon. Reprinted in part with permission, this information is ©1986-2010 by IDES. http://www.thedailygreen.com/green-homes/latest/recycling-symbols-plastics-460321