Manufacturer Requirements

Definition of Compost

There are several types of products derived from organic materials. Knowing what compost is (and what it’s not) is an important first step in ensuring that you use compost in the best way possible. Click here for the official STA Certified Compost definition for what can be considered compost.

Permits

Compost manufacturers participating in the STA Certified Compost program are required to be in compliance with all local, state and national regulations for manufacturing compost.

Certified Labs

Representative test results come from accurate compost sampling methods and from quality labs. STA Certified Compost participants must use TMECC technical sampling methods, and labs that undergo the Compost Analysis Program (CAP) quality oversight.

Frequent Testing

Testing compost often is key to staying on top of understanding a product that is constantly evolving. 
Manufacturers who produce:

Over 17,501 wet tons / year must test monthly
17,500 to 6,201 wet tons / year must test every two months
Under 6,200 wet tons / year must test every three months

Test results

STA Certified Compost manufacturers must share their test results and compost ingredients (feedstocks) upon request. Through this transparency, you can match your specific project to the compost product that works best.  Read more to better understand the test results.

Passing Test Results

For safety, all STA Certified Compost manufacturers are required to pass EPA standard limits for pathogens and metals, in every test, for every STA Certified Compost product, to remain in the program.

Higher Standards for Test Results

Some STA Certified Compost manufacturers opt to hold their products to even higher standards. These compost products must pass the standards for the Compost Consumer Use Program (CCUP) test results to remain in the CCUP program.

Sources to Buy

We are proud of our compost manufacturers who have made the grade to be included in our list of STA Certified Compost manufacturers. Ask your local source to join if you don’t see them here yet.