With Colorado marijuana testing regulations changing quickly and often, it can be hard to keep up. Here is a quick guide to the current Colorado microbial testing protocols that went into effect on February 1st, 2018.

Weight of Sample Batches for Cannabis Testing

The MED requires that all retail batches of marijuana be tested before they are sold. Below are the weights required for these sample submissions:

Harvest Batches

  • Up to 10 lbs: 4 grams
  • 10.01 lbs – 19.99 lbs: 6 grams
  • 20 lbs – 29.99 lbs: 7.5
  • 30 lbs – 39.99 lbs: 9 grams
  • 40 lbs – 99.99 lbs 11.5 grams
  • 100+ lbs 14.5 grams

Production Batches

  • Up to 1 lb: 4 grams
  • 1.01 lbs – 1.99 lbs: 6 grams
  • 2 lbs – 2.99 lbs: 7.5 grams
  • 3 lbs – 3.99 lbs: 9 grams
  • 4 lbs – 9.99 lbs: 11.5 grams
  • 10+ lbs: 14.5 grams

These samples are to be submitted to the qualified lab of your choice. Here is a link to the list of approved labs in Colorado:


Contamination Levels for Colorado Cannabis Microbial Testing

Colorado cannabis testing for microbial consists primarily of tests for E.coli, Salmonella, and Total Yeast and Mold. These are counted in Colony Forming Units, or CFUs.

There is a zero tolerance policy for E.coli and Salmonella counts, which must be under 1 CFU. Should a lab test any product that is higher than that, they are required to report it to the Colorado Department of Public Health and Environment immediately.

Total Yeast and Mold counts must be under 10,000 CFUs to qualify as passing a cannabis test for microbial content.

Retesting Failed Batches from Cannabis Lab Testing

In the event that a sample fails cannabis microbial testing, you have the ability to resubmit samples for a retest. This is where our cannabis kill-step solution from Willow Industries can really help you. We will come in and decontaminate any failed batches, and you can submit clean samples for your retests.

Colorado cannabis testing regulations require two (2) retest samples per batch to be submitted.
You may use the lab you previously did, (for the failed test), for both retest submissions. If you choose not to re-use that lab, you must send samples to two new labs. Each of these samples must contain the appropriate weight as listed above. For instance, if you sent in a 4 gram sample for the first test, each of the two retest samples must weigh 4 grams as well.

For more information on mandatory testing, check out our article on Process Validation and Sampling Procedures, or the complete Code of Colorado Regulations.