How Do Collection and Successful Recycling Mass Differ?

• Collected mass
• Recovered after sorting

What you will learn

• Tell what goes into the bin apart from what is actually recycled.
• Say where the difference goes.
• Avoid mixing up the contamination rate with the recycling rate.

Before you start

It helps to read the article on recycling-bin contamination first; this one reuses that idea to talk about mass.

Why does what goes in the bin differ from what is recycled?

Because the bin holds things that cannot be recovered. According to Pinellas County, the county's 2024 composition study put the contamination rate at 21.7%, meaning about one pound in every five pounds put in kerbside and drop-off bins could not be recycled.

That is one county's figure. Elsewhere the rate may differ.

Where does the difference go?

Some of it is removed at the sorting facility, and some can take a whole load with it. According to the Wasatch Integrated Waste Management District, the facility described has a quality-control sorter who removes contamination before the storage bunkers, and only material with value is recovered, baled and sold. According to UW Recycling, if a load holds too much contamination the whole load, clean material included, is sent to landfill.

Track collected mass, material recovered after sorting and mass counted as recycled separately. According to Pinellas County, sorted bales are sold to buyers who turn the material into new products. Weighing a bale measures sorting output; it does not establish the mass of new products eventually made.

• Checkpoint
• Removed part
• Whole load discarded

How does the contamination rate differ from the recycling rate?

The two rates measure different things. According to Pinellas County, a county's recycling rate is the tons counted as recycled divided by the total tons disposed and recycled, and in 2024 the county's rate was 62%. The contamination rate speaks only about the recycling bin, while the recycling rate counts garbage and recyclables together.

So you cannot read 62% as 62% of the bin's contents being recycled, and you cannot use 21.7% to work out the county's recycling rate.

• Contamination rate: recycling bin only
• Recycling rate: garbage and recyclables together

Real-world example

Picture a collection bin full of paper, bottles and a few items the programme does not accept. This is a hypothetical walk-through to follow the two masses. Weighing the collected contents, excluding the bin itself, gives collected mass. After the facility removes unaccepted items, weighing the remainder gives mass recovered after sorting. The bale goes to a buyer for further processing; do not rename its weight as the mass of finished recycled products. Follow the same batch and state the measurement stage when comparing these quantities.

Common misunderstandings

Putting something in the bin does not mean it is recycled. An item that cannot be recovered is part of the collected mass but not of the recycled mass.

A county's recycling rate also does not tell you what share of the bin is recycled. The two rates have different denominators.

Frequently asked questions

What is collected mass?

The mass actually collected into the recycling route, including contaminants and excluding the bin itself.

What is recycled mass?

State the measurement stage and accounting method. A sorted bale is material recovered for further processing, not automatically the mass of new products.

Is the contamination rate the recycling rate?

No. They measure different things and use different denominators.

Summary

• Collected mass may include contaminants; rejected items do not continue in the recovered-material stream.
• Distinguish collection, recovery after sorting and manufacture of new products; always state the measurement stage.
• The contamination rate and the recycling rate are two different numbers.