The audit that rewrote our intake form
A chemical blender audited us for two days in January and found nothing wrong with our wash records. They found something wrong with the question we ask before the wash.
- Sheet
- 90
- Revision
- 2026-10
- Scale
- 1:1
- Drawn at
- Peoria IL
We have hosted four customer audits. This was the useful one, because the auditor ignored the thing we were proud of and went looking at the thing we had never examined.
They spent the first morning on wash bay records — cycle logs, temperatures, operator initials, pH readings on neutralisation, lab results on food-grade releases. All of it checked out, which we expected, because that paperwork is the product as much as the container is. Then after lunch the auditor asked to see the form a customer fills in when they sell us containers, and spent the rest of the day on that single page.
“Your cleaning records are excellent. They are records of a decision you made with incomplete information.”
— The auditor, somewhere around 2pm
The gap
Our intake form asked for last contents. It did not ask at what concentration, whether the container had ever held anything else, how it had been stored since being emptied, or whether it had been rinsed and by whom. All four of those change the wash cycle we should run and the grade the container can reach — and we were inferring them from a photograph and a smell test.
The smell test is good. One of our graders can identify glycol, vegetable oil, surfactant and solvent residue faster than any instrument we could afford. But it tells you what is in the container now, not what has been in it over eight years, and absorbed history is exactly the thing that disqualifies a container for food-grade service forever.
The six questions we added
- What was the last product, by name and concentration — not category. 'Caustic' covers 5% and 50%, and they are different containers afterwards.
- Has this container held anything other than that product? If yes, what and roughly when?
- Has it been rinsed? By whom, with what, and is there a record?
- How has it been stored since it was emptied — indoors, outdoors, covered, stacked, how long?
- Has it ever been modified, repaired or rebottled, and by whom?
- Is the UN marking legible, and can you photograph the plate?
None of these are difficult to answer and all of them move the price. Question four turned out to be the surprise: storage history predicts grade better than last contents does. A container that held fertiliser and sat indoors beats a container that held water and spent two summers in direct sun, every time, because UV plus flex is what crazes a bottle.
What it changed in practice
| Before | After | Effect |
|---|---|---|
| Last contents, one free-text line | Product, concentration, prior contents | Fewer wrong cycles, fewer regrades |
| Wash cycle chosen at the bay | Cycle chosen at intake, confirmed at the bay | Caustic runs dropped 12% |
| Storage history unasked | Storage history required | Grade prediction accuracy up sharply |
| UN plate photographed sometimes | Photographed always, filed against the serial | No more unreadable-plate disputes |
| Rinse records optional | Rinse records requested and priced in | Customers started sending them |
The last row is the one that pays for itself on both sides. Once we started asking for rinse records and paying a better band for containers that had them, customers started producing them. A documented rinse often moves a container up a price band by more than the rinse cost to perform.
Selling containers to anybody, not just us
Answer those six questions in writing before you accept a quote. It will change what you get offered, and it tells you immediately whether the buyer knows what they are doing.