Most cosmetic packs carry an open-jar icon followed by a number and the letter M. New brand owners often ask their manufacturer whether to print it or to use an expiry date instead. The answer depends on the product's stability and the target market, and it should never be copied from a competitor. This guide explains the difference, who sets the period, and how it applies to an argan oil product.
What does the PAO symbol mean?
PAO stands for Period After Opening: how long the product stays safe and pleasant to use once the seal is broken. The number does not say when the product was made. It tells the consumer how many months to use it after first opening.
The minimum durability date, by contrast, refers to the unopened product stored properly. They are two different concepts, and one does not automatically replace the other.
When a date, when PAO?
Under EU Cosmetics Regulation 1223/2009, a minimum durability date is shown when the product's stability is under thirty months; beyond that, indicating the period after opening is enough. That is the EU rule. Gulf markets and others have their own registration and labelling requirements, so check with the local authority before printing.
| Element | What it tells the buyer | What it relies on |
|---|---|---|
| Minimum durability date | How long the sealed product keeps its quality | Stability tests in the final pack |
| PAO symbol | Months of use after opening | Safety assessment, microbial protection, packaging |
| Batch number | Which batch the product came from | Production records and traceability |
Who sets the number?
A brand does not pick a figure because it sounds good in marketing. It is a professional decision made by the safety assessor from stability data, microbiological tests and expected use. So ask early in development: who signs off this period and which tests support it? The document that gathers this evidence is covered in our cosmetic product safety assessment guide.
Why oils are a special case
Argan oil is mostly anhydrous, so microbial growth is less of a risk than in a cream or emulsion. That does not make its life unlimited. The deciding factor is oxidation, sped up by heat, light and air. Each opening lets in fresh air, and each contact with skin can introduce impurities. The period therefore depends on the whole formula: is an antioxidant added? Is there a water phase? Is the bottle tinted and well sealed?
The dispensing system matters too. A dropper that touches skin and goes back into the oil is not the same as a closed pump, as we explain in our dropper, pump or spray comparison.
Practical steps
- Define your markets before designing the artwork.
- Request stability data: test length, conditions, and the pack used.
- Ask about challenge testing if any water phase is present.
- Choose the packaging before the period; changing the bottle means reassessment.
- Document the decision and who made it.
- Check the symbol is legible before printing.
Common mistakes
- Copying a competitor's PAO because the ingredients look similar.
- Printing a long period because it sells, then facing rancid-smell complaints.
- Confusing manufacturing date with expiry date.
- Swapping the dropper or cap after the period was validated.
FAQ
Must every product carry a PAO?
Not always. Under the EU rule, under thirty months of stability calls for a date; beyond that, PAO is enough. Check your market.
Can the manufacturer set the figure alone?
It supplies data and tests, but the decision rests on the safety assessment. Ask for the documents.
Does the figure change with bottle size?
It can, because the air-to-oil ratio and opening frequency differ.
What is the batch number for?
It does not replace a date, but it lets you trace the product if a complaint arrives.
Bottom line
The after-opening period is a commitment to the consumer, backed by data. Gather that evidence early with your manufacturer. If you are planning an argan oil range, you can request a quote and we will go through specifications, packaging and the documents your market requires.
