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Prove your product is clean

Lab testing in plain English: what a COA is, how to order one, and how to show it to customers.

4 lessonsabout 46 minutes

What you finish with

A written testing policy, an account with an independent lab, and published per-lot results customers can look up.

Lessons

  1. 01Reading a certificate of analysis

    14 min

    A COA is a lab's report on one specific lot. We go through it field by field — sample identity, method, result, specification, date, signature — so you can tell a real document from a decorated one in under a minute.

    • Every field on a COA and what it means
    • Matching lot numbers to physical stock
    • Signs of an altered or reused certificate
  2. 02Which tests to order

    12 min

    Identity and purity are the baseline. Depending on the material and format you may also need sterility, endotoxin and residual-solvent testing. Learn what each test answers and which ones your buyers will ask about.

    • Identity, purity and quantitation basics
    • Sterility and endotoxin: when they apply
    • Setting your own internal specification limits
  3. 03Choosing and working with a lab

    11 min

    Your lab must be independent of your supplier and accredited for the methods you're buying. We cover how to open an account, submit samples correctly, and budget testing per lot rather than per year.

    • Accreditation and method scope questions
    • Sample submission and chain of custody
    • Per-lot testing cost planning
  4. 04Publishing results without overselling

    9 min

    Publish the full document, tied to the lot on the label, with no commentary that turns a test result into a claim. This is the single most persuasive trust asset you will own.

    • Lot-lookup page structure
    • What not to write around a test result
    • Handling an out-of-specification lot publicly

Templates included

  • COA review checklist
  • Testing policy template
  • Lot-lookup page structure

Mistakes to avoid

  • Publishing only the supplier's own paperwork
  • Testing one lot and reusing the result forever
  • Quietly shipping a failed lot