Plastic products are printed with numbers 1–7 depending on the type of resin. Type 1 plastic, PET (or PETE): polyethylene terephthalate, is commonly found in soft drink and water bottles. Type 2, HDPE: high-density polyethylene is found in most hard plastics such as milk jugs, laundry detergent bottles, and some dishware. Type 3, PVC or V (vinyl), includes items like shampoo bottles, shower curtains, hoola hoops, credit cards, wire jacketing, medical equipment, siding, and piping. Type 4, called LDPE, or low-density polyethylene, is found in shopping bags, squeezable bottles, tote bags, clothing, furniture, and carpet. Type 5 is PP which stands for polypropylene and makes up syrup bottles, straws, Tupperware, and some automotive parts. Type 6 is PS: polystyrene and makes up meat trays, egg cartons, clamshell containers and compact disc cases. Type 7 includes all other plastics like bulletproof materials, 3- and 5-gallon water bottles, and sunglasses.Types 1 and 2 are the most commonly recycled.
Some industries, like the renewable energy industry and solar photovoltaic technology in particular, are being proactive in setting up recycling policies even before there is considerable volume to their waste streams, anticipating future demand during their rapid growth.
In order to meet recyclers' needs while providing manufacturers a consistent, uniform system, a coding system is developed. The recycling code for plastics was introduced in 1988 by plastics industry through the Society of the Plastics Industry, Inc. Because municipal recycling programs traditionally have targeted packaging—primarily bottles and containers—the resin coding system offered a means of identifying the resin content of bottles and containers commonly found in the residential waste stream.
Many recycling bins are designed to be easily recognizable, and are marked with slogans promoting recycling on a blue or green background. Others are intentionally unobtrusive. Bins are sometimes different colors so that user may differentiate between the types of materials to be placed in them. While there is no universal standard, the color blue is commonly used to indicate a bin is for recycling in public settings.
The design objectives behind the bin were efficient use of space and safety: to provide at least as much space as the older round bins, whilst reducing the risk of injury caused by moving it. This is important for both the householder and the waste collector, who risked injury through lifting the traditional bin or from sharp, or possibly contaminated objects in garbage bags. Standardisation of dimensions is important because the bins must be lifted by a standard sized hoist on the dustcart. The bins are lifted by the lip at the front which must be designed for maximum stiffness and mechanical strength. The underside of the lip is therefore reinforced by numerous ribs in the case of the thermoplastic bins. Steel bins have a much simpler lip owing to the properties of steel.