What do the numbers on plastic products mean?

Have you ever seen the symbols on plastic products that look like a recycling logo with a number inside? These are called the material identification codes. They tell plastic manufacturers and recyclers which polymers are present in the plastic product. These symbols do not have anything to do with the number of times the plastic can be recycled, as is commonly believed.

The coding system is used around the world by recyclers to separate and sort plastics so that they can be processed according to the main polymer present.

The numbers on the identification symbol range from one to seven. These numbers are contained within three chasing arrows, forming a triangle around the number. The acronym of the polymer is also displayed underneath the triangle.

1. PET – Polyethylene terephthalate

The symbol with a 1 is used for PET plastic. PET is one of the most common polymers used for food and beverage packaging. It is used to make carbonated drink bottles, water bottles, plastic jars, punnets, trays, strapping tape and more. PET is widely recycled in South Africa and around the world.  For more info visit www.petco.co.za

2. PE-HD (or HDPE) – High-density polyethylene

The identification code with a 2 is used for PE-HD plastic. This is a hard and strong form of polyethylene that is used to manufacture milk bottles, fruit juice bottles, plastic drums, buckets, crates, bins and shampoo bottles. PE-HD is recycled in South Africa. Its strength and durability make it ideal for products that need to withstand wear and tear. For more info on the recycling of PE-HD visit www.polyco.co.za

3. PVC – Polyvinyl chloride

The symbol with a 3 represents PVC – a sturdy and hard plastic polymer. It is used to create irrigation pipes, tamper-proof medicine seals, shrink-wrapping, conduit, toys, plastic gutters and more. PVC is quite difficult to recycle and requires special machinery. Many small-scale recyclers in South Africa cannot process PVC, so plastics manufacturers have started to replace PVC products with PET. For more information visit www.savinyls.co.za

4. PE-LD (or LDPE) – Low-density polyethylene

The identification code with a 4 is used for PE-LD plastics and products such as grocery bags, packets, cling film, bubble wrap and sandwich bags. PE-LD is a flexible polymer that is widely recycled in South Africa. Previously, this type of plastic could jam the sorting machines at recycling facilities, but this is not often the case anymore.  For more info on the recycling of PE-HD visit www.polyco.co.za

5. PP – Polypropylene

The symbol with a 5 depicts PP plastic. This is a temperature-resistant polymer that is used to manufacture ice cream containers, kettles, straws, microwave dishes, garden furniture, bottle caps and takeaway cutlery. PP is also commonly recycled in South Africa.  For more info on the recycling of PP visit www.polyco.co.za

6. PS – Polystyrene

The code with a 6 is used for polystyrene. There are two types of PS – expanded PS and a hardened PS. Expanded PS is the foam-like material used to make packaging fillers and takeaway food containers. The hardened PS is used to manufacture coathangers, bread tags and yoghurt cups. PS is accepted by recycling facilities in South Africa. Visit www.polystyrenesa.co.za for more information

7. Other

The symbol with a 7 is used to denote any other type of plastic polymer. The symbol will display a range of acronyms beneath the triangle, such as ABS, E/VAC, POM, PC, PETG, PA and a combination of these acronyms. Plastics with this code are often made from a mixture of polymers which makes them difficult to recycle, or not recyclable at all.   Many of these plastics are used in plastic timber manufacture where they are combined with wood shavings to produce jungle gyms, walkways which will last for years despite weather conditions, outdoor furniture etc.

In South Africa, materials are only recycled if there is a suitable end-market for the recyclate. These identification codes are used by recyclers to sort the plastics into similar batches for processing.