In short
Most formula errors are small slips: a decimal, a forgotten dilution, a line skipped. The reference guide lists the common ones. This study guide gives you a flawed sheet to audit, because finding errors is a separate skill from avoiding them.
What you will learn
- Audit a batch sheet for common errors
- Add quick checks to your own process
Before this lesson: Perfume Dilution Practice Problems
What to look for as you read
- Which errors a simple total check would catch, and which it would miss.
- How each type of error would show up on the strip.
Practical exercise: Audit a flawed batch sheet
This invented batch sheet is meant to total 20.00 g of concentrate. Find five errors.
| Line | Parts per 1,000 | Stock | Sheet says weigh (g) |
|---|---|---|---|
| A | 500 | Neat | 10.00 |
| B | 300 | Neat | 0.60 |
| C | 150 | Neat | 3.00 |
| D | 40 | 10% | 0.80 |
| E | 10 | 1% | 0.20 |
| Total | 1,000 | 14.60 |
Answers, once you have tried: B should be 6.00 g, a decimal slip. D's pure amount is 0.80 g, so at 10% it should weigh 8.00 g. E's pure amount is 0.20 g, so at 1% it should weigh 20.00 g, which is impractical: use a stronger stock or neat. The total shows that something is wrong, and the corrected pure material reaches 20.00 g only with these lines fixed. Finally, no sheet with stocks can weigh the same as its pure total, and this one does not say which it means, which is a fifth error in itself.
Now write your own pre-weighing checklist of no more than five checks, and use it on your next batch.
You have done this well if you found the slips before reading the answers, and your checklist would have caught them.
Knowledge check
Written and reviewed by the RUŌOD Lab team. This is general education, not legal, regulatory, medical or safety advice. Example dilutions and exercises are for learning, are not validated products, and have not been safety-assessed. Completing a lesson confers no qualification. How we check these lessons.