What Is Stability?
Stability carries two distinct meanings depending on the product group. In FURNITURE, stability means resistance to tipping over: loads defined in the standard are applied to the product at defined points, and whether it tips is observed. In COSMETIC AND PHARMACEUTICAL PRODUCTS, stability is monitoring under controlled temperature and humidity conditions whether the product retains its physical, chemical and microbiological properties over its shelf life.
Purpose of Stability
In furniture, the purpose is to verify the product does not tip over under foreseeable use, particularly children climbing on it — tipped-over cabinets and TV units are a serious source of injury. In cosmetics and pharmaceuticals, the purpose is to support the declared shelf life and storage condition with data.
Which Products Is Stability Applied To?
- Cabinets, bookcases, chests of drawers and TV stands
- Tables and chairs
- Cosmetic products (cream, lotion, shampoo)
- Pharmaceutical formulations and packaged products
- Food supplements
In Which Sectors Is Stability Used?
Standards Related to Stability
- TS EN 1022 (seating — determination of stability)
- TS EN 1730 (tables — stability tests)
- TS EN 16121 / 16122 (storage furniture — stability)
- ICH Q1A(R2) (stability testing of new drug substances and products)
- ICH Q1B (photostability)
- ISO 18811 (guidelines on stability testing of cosmetic products)
Stability Conditions
- Furniture
- Vertical and horizontal loads defined in the standard, applied at defined points
- Pharmaceutical — long term
- Long-term storage condition defined in ICH Q1A, chosen according to climatic zone
- Pharmaceutical — accelerated
- Accelerated condition defined in ICH Q1A; typically monitored for six months
- Cosmetics
- Monitoring under room, high-temperature, low-temperature and cyclic conditions
Equipment for Stability
- Stability (tip-over) test platform and loading rigs
- Climate chambers (temperature and humidity controlled)
- Photostability chamber
- HPLC and analytical measurement systems
- pH meter, viscometer and microbiological facilities
Sample Requirements for Stability
- A fully assembled product for furniture; the declared use class must be provided
- Specimen with its market packaging for cosmetics and pharmaceuticals
- A separate specimen is required for each time point to be pulled
- Formulation, packaging material and batch information must be provided
Duration of Stability
The furniture stability test is short. Cosmetic and pharmaceutical stability studies are inherently long: the accelerated condition typically runs six months, and the long-term study runs for the declared shelf life, with specimens pulled at defined time points.
Stability Procedure
- 1For furniture, the product is placed on the defined floor and conditioned.
- 2Vertical and horizontal loads are applied at the points defined in the standard; tipping is observed.
- 3For cosmetics and pharmaceuticals, specimens are placed in chambers at the defined conditions.
- 4Specimens are pulled at the defined time points.
- 5Appearance, pH, viscosity, active substance content, degradation products and microbiological properties are measured.
- 6Results are assessed as a trend over time.
Stability Acceptance Criteria
In furniture, the acceptance criterion is that the product does not tip over under the defined loads. In cosmetics and pharmaceuticals, it is that specification limits are maintained over the shelf life; the limits are defined in the product's own specification, and come from the pharmacopoeia monograph where one exists.
Evaluation of Results
In furniture, each loading point is assessed separately; passing at one point does not cover another. In pharmaceuticals and cosmetics, accelerated results alone do not determine shelf life — they support the long-term data; if a significant change is seen, an intermediate condition study is required.
Stability Report
- Product identification and test scope
- Loads applied, points and tip-over observation for furniture
- Storage conditions and time points for cosmetics and pharmaceuticals
- Measurement results for each time point
- Trend assessment and conclusion
Accreditation
EUROLAB holds internationally recognised accreditation obtained from accreditation bodies party to the IAF and ILAC multilateral recognition arrangements, under ISO/IEC 17025 for laboratory testing, ISO/IEC 17020 for inspection and surveillance, and ISO/IEC 17021-1 and ISO/IEC 17065 for system and product certification. This chain ensures the reports and certificates issued are accepted worldwide.
Whether this test can be offered within accredited scope depends on your product and the standard applied; since accreditation is method-based, the scope is confirmed in writing at the quotation stage.
Scope and authorisationsRelated Regulations
- (EU) 2023/988 General Product Safety Regulation
- (EC) 1223/2009 Cosmetic Products Regulation
- 2001/83/EC Directive on Medicinal Products for Human Use
Kozmetik Testleri — What Does This Testing Field Cover?
The section below describes the field that the Stability test belongs to; the conditions and acceptance criteria of this particular test are given in the sections above. The scope specific to your product is confirmed in writing at the quotation stage.
Cosmetics testing shows that a product stays microbiologically safe throughout its use, delivers the performance it claims and contains no restricted substances. There is NO PRODUCT APPROVAL in this family: no authority approves a cosmetic product; responsibility rests entirely with the manufacturer and with the responsible person established in the EU.
This responsibility model shapes how the field works. Before the product is placed on the market a product information file (PIF) is prepared, a safety assessment (CPSR) is carried out and notification is completed. Inspection comes afterwards and asks for the file; if the file is incomplete the product is withdrawn from the market. Test reports form the evidence base of that file.
On the microbiological side there are two different questions and each is answered by a separate test. The CURRENT microbiological quality of the product is measured by enumeration and testing for specified microorganisms. The EFFECTIVENESS of the preservative system is examined by deliberately inoculating the product with microorganisms (challenge test): can the product resist repeated contamination throughout its use? A jar of cream is touched by a finger at every use; the preservative system must cope with that.
On the performance side, claim substantiation studies are carried out. For sunscreens, determination of SPF and UVA protection and measurement of water resistance are mandatory and are the basis of the value declared on the label. Evidence is also produced by in vivo or in vitro methods for claims such as moisturisation, appearance of wrinkles, hair care and colour retention.
On the chemical side, banned and restricted substances are screened: heavy metals, prohibited colorants, preservative concentrations, UV filter levels and contaminants such as nitrosamines. Products containing nanomaterials carry a separate notification obligation.
The BAN ON ANIMAL TESTING is the most defining constraint of the field. Animal testing cannot be carried out on finished products or ingredients, and a product tested on animals cannot be placed on the market. Alternative in vitro methods (reconstructed human skin models, cell culture based tests) are therefore at the centre of the field, and toxicological assessment rests largely on existing data, read-across approaches and in vitro results.
Stability and packaging compatibility studies determine shelf life and the period after opening (PAO). The interaction of the product with its packaging is also assessed: an active substance may migrate into the packaging, and substances that should not be present may pass from the packaging into the product.
On the process side, good manufacturing practice is demonstrated through ISO 22716; this is separate from product testing but a mandatory part of the file.
Method groups in this field
Microbiological quality
Enumeration of aerobic mesophilic bacteria, yeasts and moulds; testing for Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans and E. coli.
Preservative efficacy
Resistance of the preservative system to repeated contamination by challenge test (ISO 11930).
Sun protection
In vivo SPF determination, in vitro UVA protection determination, water resistance and critical wavelength measurements.
Chemical analysis
Heavy metals, banned and restricted substances, quantification of preservatives and UV filters, contaminant screening.
Safety assessment
In vitro irritation and sensitisation methods, toxicological risk assessment, exposure calculations.
Stability and compatibility
Real-time and accelerated stability, packaging compatibility, PAO determination, sensory and physicochemical monitoring.
Commonly confused in this field
- There is NO CE marking on cosmetics; conformity is demonstrated through the PIF, the safety assessment and notification.
- The responsible person must be established in the EU; unless the exporter arranges this, the product cannot be placed on the market.
- Microbiological quality and preservative efficacy are different tests; a product that comes out clean may still have a weak preservative system.
- The animal testing ban covers ingredients too; animal test data generated for another market creates a problem of use.
- An SPF claim must be supported by measurement; a formulation change requires a new measurement.
- A change of packaging may require the stability and compatibility studies to be repeated.
Which decisions these results support
- The product information file and the safety assessment
- Verification of the preservative system design
- Substantiation of SPF and efficacy claims
- Determining shelf life and the period after opening
- Compliance with destination market restrictions for export
Related Tests
Frequently Asked Questions About Stability
We anchor the cabinet to the wall — is a stability test still needed?
Yes. Product standards address both anchored and unanchored conditions, since the user may not fit the anchor. Supplying the anchoring hardware with the product and clear instructions is a separate compliance matter.
Does accelerated stability determine shelf life?
Not on its own. Accelerated data gives an early prediction and can support a provisional shelf-life claim, but the final shelf life is supported by long-term study data.
Are stability and challenge testing the same thing in cosmetics?
No. Stability studies track the product's change over time; challenge testing (preservative efficacy) deliberately inoculates the product with micro-organisms to show the preservative system works. Both are required together in the Product Information File.