What Is UVA?
The UVA test is an accelerated ageing test that represents the 295–365 nm region of the solar spectrum using UVA-340 fluorescent lamps. It is the fluorescent UV option with the best correlation to outdoor exposure.
Purpose of UVA
The purpose is to realistically assess UVA-induced colour change, gloss loss and surface degradation in outdoor materials.
Which Products Is UVA Applied To?
- Exterior facade paints
- Automotive exterior surfaces
- Plastic profiles and panels
- Coated textiles
In Which Sectors Is UVA Used?
Standards Related to UVA
- ISO 4892-3
- ASTM G154fluorescent UV accelerated aging test
- ISO 16474-3
UVA Conditions
- Lamba
- UVA-340
- Radiation
- Standard defined intensity at 340 nm
- Cycle
- Defined duration of light and condensation phases
- Black panel temperature
- Defined in standard
Equipment for UVA
- Fluorescent UV chamber (with UVA-340 lamps)
- Calibrated radiometer
- Colour and gloss meter
Sample Requirements for UVA
- Initial colour and gloss must be measured
- A reference sample must be kept
- Cutting must be done to panel size
- Generally at least three specimens
Duration of UVA
Applied in stages of 250 – 2000 hours depending on the specification.
UVA Procedure
- 1Initial measurements are taken.
- 2The UVA-340 lamp and irradiance setting are verified.
- 3Samples are placed on the panels.
- 4Cycles are run for the defined duration.
- 5Interim and final measurements are taken.
UVA Acceptance Criteria
The acceptance criterion is given in the specification as maximum colour difference and gloss loss.
Evaluation of Results
Colour difference and gloss loss are measured. Results are comparable with tests performed using the same lamp type.
UVA Report
- Applied standard and lamp type
- Irradiance and cycle programme
- Exposure duration
- Colour difference and gloss values
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
- Paint and plastics product specifications
Environmental and Climatic Testing — What Does This Testing Field Cover?
The section below describes the field that the UVA 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.
Environmental testing shows whether a product withstands ambient factors such as temperature, humidity, pressure, solar radiation, dust, water and corrosive atmospheres. The aim is not to break the product but to bring forward, in ACCELERATED form, the conditions it will meet over its life.
Test profiles are derived from the product's real exposure, and that derivation is the actual engineering work of the field. A device operating in an enclosed office and one mounted on a pole are not tested with the same profile. The IEC 60068 series defines general methods, MIL-STD-810 military profiles, RTCA DO-160 aviation profiles and the ISO 16750 series location-based automotive profiles. A test applied without a profile selection produces both unnecessary cost and false confidence.
Temperature tests simulate three separate phenomena and all three produce different failure modes. Steady high/low temperature tests whether the material can operate at that temperature. Temperature CYCLING creates fatigue at joints between materials with different expansion coefficients — solder cracks appear here. Thermal SHOCK intensifies this effect through an abrupt transition.
There is a distinction in humidity testing too. Steady damp heat shows the diffusion of moisture into the material and its effect on insulation properties. Cyclic damp heat creates condensation: water droplets form on the cooling surface, and this is far more aggressive than dry humidity. Water ingress into enclosures, increased leakage current and corrosion usually appear in the cyclic test.
Dust and water protection is a separate body of work and is expressed by the IP code. The point to note here is that an IP test is not a DURABILITY test: it shows that protection is provided under defined and short-duration conditions, not resistance to long-term immersion or pressure washing.
The most common mistake in this family is translating a test result directly into a LIFE PREDICTION. Accelerated tests are designed for comparison and design verification; a reliable conversion between hours in a chamber and years in the field can only be established with a material-specific acceleration model calibrated against field data.
Functional monitoring determines the value of the test. Keeping a product in a temperature chamber and then switching it on does not show what happened DURING the test. In critical applications the product is operated throughout the test and its parameters are monitored; intermittent faults that appear and disappear can only be caught this way.
Method groups in this field
Temperature
Dry heat, cold, change of temperature and thermal shock; steady and cyclic profiles.
Humidity
Steady damp heat and cyclic damp heat; cycles with condensation are more aggressive.
Water and dust
IP protection tests: dripping, spraying, jets, immersion and dust tightness.
Radiation and ageing
Accelerated ageing by xenon arc and fluorescent UV, solar radiation simulation.
Pressure and altitude
Low pressure (altitude) and rapid pressure change tests.
Corrosive atmosphere
Salt spray, mixed flowing gas corrosion (simulating industrial atmospheres), mould and fungus tests.
Commonly confused in this field
- Test duration cannot be converted into field life; a conversion made without an acceleration model is misleading.
- Temperature cycling and steady temperature produce different failure modes; neither replaces the other.
- If the product is not operated during the test, intermittent faults remain invisible; functional monitoring determines the value of the test.
- IP protection is not evidence of durability; it shows protection under defined and short-duration conditions.
- A test applied without profile selection both increases cost and gives false confidence.
- The mounting and orientation arrangement affects the result; the report must document it.
Which decisions these results support
- Design verification and qualification
- Declaration of the protection class and operating temperature range
- Reproducing field failures in the laboratory and root cause analysis
- Supplier component approval
- Decisions on warranty period and storage conditions
Related Tests
Frequently Asked Questions About UVA
According to which standard is UVA made?
UVA is executed in scope ISO 4892-3, ASTM G154 and ISO 16474-3. The limit values and acceptance criteria to be applied are defined in the product standard; The version valid for your product is confirmed in writing at the offer stage.
Which products does UVA apply to?
Mainly applied to Exterior facade paints, Automotive exterior surfaces, Plastic profiles and panels and Coated textiles. Whether your product is included in the scope is determined by examining its technical specifications and intended use.
Under what conditions is UVA done?
The determining parameters are: Lamba — UVA-340, Radiation — Standard defined intensity at 340 nm and Cycle — Defined duration of light and condensation phases. The full terms are in the "Test Conditions" section on the page and vary depending on the product standard.
What kind of sample is needed for UVA?
Initial colour and gloss must be measured, A reference sample must be kept and Cutting must be done to panel size. The number of samples is determined according to the product standard and the scope to be reported.
How long does UVA take?
Applied in stages of 250 – 2000 hours depending on the specification. This duration belongs to the experiment itself; sample preparation, queuing and reporting are also evaluated. A realistic schedule for your product is given in the offer.
What is the UVA result called "appropriate"?
The acceptance criterion is given in the specification as maximum colour difference and gloss loss.










