UV Accelerated Weathering Testing with Controlled Light and Moisture Cycles
The DERUI UV accelerated weathering tester exposes specimens to fluorescent UV radiation, elevated temperature, condensation and—where specified—water spray. It helps laboratories compare how plastics, coatings, rubber, textiles and other nonmetallic materials respond to controlled accelerated weathering conditions.
Programmable cycles and irradiance control support repeatable material screening, formulation comparison and quality-control work. The equipment can be configured around the specimen format and the exposure method required by your material or customer specification.
What the Tester Reproduces—and What the Results Mean
Fluorescent UV weathering equipment concentrates on the short-wave UV, heat and moisture stresses that drive many outdoor degradation mechanisms. Depending on the material and evaluation method, laboratories can track color change, gloss loss, chalking, cracking, embrittlement, strength loss or other defined property changes.
Controlled exposure
- Fluorescent UV radiation at a defined irradiance
- Black-panel or chamber temperature control
- Condensation to reproduce prolonged surface wetness
- Water spray when required by the selected procedure
- Repeatable programmed transitions between cycle steps
Useful decisions
- Compare formulations, coatings or suppliers
- Screen materials before longer outdoor exposure
- Investigate known UV- and moisture-related failures
- Verify production consistency against an approved control
- Generate documented exposure records for customer programs
Key Equipment Functions
UVA-340 lamp system
UVA-340 lamps are used to reproduce the short-wave UV portion of terrestrial sunlight. Lamp type must be selected from the applicable material method rather than chosen only for faster damage.
Irradiance monitoring
Closed-loop monitoring helps maintain the programmed irradiance as lamps age, improving consistency between exposure runs and supporting routine verification.
Condensation and spray
Condensation creates sustained surface wetness comparable to dew exposure. A spray stage can be configured when the selected cycle calls for thermal shock, erosion or rain simulation.
Programmable controller
The touchscreen controller manages UV, dark, condensation and spray steps, including time, temperature and irradiance setpoints for repeatable operation.
Specimen presentation
Specimen holders should expose the required surface consistently while unused openings are closed with blank panels. Custom holders can be reviewed for unusual parts.
Operational protection
Door interlocks, alarm handling and automatic protection functions reduce the risk of unintended UV exposure or operation outside configured limits.
Published Model Configuration
| Parameter | Benchtop configuration | Full-size configuration |
|---|---|---|
| Published chamber size | 450 × 500 × 600 mm | 850 × 950 × 1400 mm |
| Fluorescent UV lamp | UVA-340 | UVA-340 |
| Published temperature range | 25°C to 70°C | 25°C to 80°C |
| Published irradiance range | 0.35–0.70 W/m²/nm | 0.35–0.70 W/m²/nm |
| Programmable functions | UV exposure, condensation and water spray | UV exposure, condensation and water spray |
| Controller | Touchscreen programmable control | Touchscreen programmable control |
| Protection | Door interlock and automatic shutdown functions | Door interlock and automatic shutdown functions |
| Power supply | Configured for destination voltage and frequency | Configured for destination voltage and frequency |
Specification note: confirm whether the stated dimensions are working-space or equipment dimensions before quotation. Available irradiance, temperature, lamp, spray, specimen-holder and data functions depend on the ordered configuration and governing test method.
UV Weathering Standards and Method Selection
The equipment provides the controlled functions needed for fluorescent UV exposure, but the standard alone does not create one universal test. The material specification or customer procedure must define the lamp, irradiance, temperature, moisture sequence, duration, specimen preparation and evaluation criteria.
| Method | Typical scope | What to confirm |
|---|---|---|
| ASTM G154 | Operation of fluorescent UV lamp and water apparatus for exposure of materials | Applicable cycle, lamp type, irradiance, temperature and moisture step |
| ISO 4892-3 | Fluorescent UV lamp exposure of plastics using radiation, heat and water | Method, lamp, exposure conditions and evaluation standard |
| ISO 16474-3 | Fluorescent UV exposure of paints, varnishes and coatings | Coating-specific procedure and property evaluation |
| ASTM D4329 | Fluorescent UV exposure of plastics | Product specification, cycle and post-exposure measurements |
| ASTM D4587 | Fluorescent UV-condensation exposure of paint and related coatings | Cycle, specimen preparation and coating failure criteria |
| SAE J2020 | Accelerated exposure of automotive exterior materials using fluorescent UV and condensation apparatus | Automotive program requirements and reporting conditions |
For a detailed explanation of the basic practice, read DERUI’s ASTM UV resistance testing guide. If full-spectrum sunlight simulation is required, compare the application with a xenon arc weathering test chamber rather than assuming the two light sources are interchangeable.
Recommended Test Workflow
- Define the methodIdentify the material standard, end-use environment, control specimen and properties to be measured.
- Select the lamp and cycleConfirm fluorescent UV lamp type, irradiance, exposure temperature, condensation or spray stage and total duration.
- Prepare specimensCondition, label and mount samples consistently; record initial color, gloss, mass, strength or other baseline properties.
- Program and verifyEnter the approved sequence and verify sensors, water supply, irradiance calibration and alarm settings before exposure.
- Monitor the runDocument interruptions, lamp changes, water conditions and any deviation from the approved procedure.
- Evaluate consistentlyCondition exposed specimens as required, compare them with controls and report results using the specified measurement method.
Materials and Applications
Coatings and paints
Compare gloss retention, color change, chalking, cracking, blistering and adhesion after a defined fluorescent UV and moisture exposure.
Plastics and polymers
Screen resin formulations, stabilizers and pigments for discoloration, embrittlement, surface cracking and mechanical-property change.
Automotive materials
Evaluate exterior polymer parts, coatings, seals, trim and selected interior materials under the applicable OEM or industry procedure.
Rubber and sealants
Investigate surface cracking, hardness change and loss of elasticity caused by combined UV, heat and moisture stresses.
Textiles and outdoor products
Assess color retention and material degradation where the chosen textile or product specification permits fluorescent UV exposure.
Research and quality control
Compare new formulations with an approved control and monitor production consistency without claiming a universal outdoor-life conversion.
Information Needed to Configure the Tester
Test information
- Material and end-use application
- Applicable ASTM, ISO, SAE or customer method
- Lamp type and irradiance setpoint
- UV, condensation and spray sequence
- Exposure duration and evaluation intervals
Specimen and site information
- Specimen dimensions, thickness and quantity
- Required holder geometry and exposed area
- Laboratory voltage and frequency
- Water quality and drainage conditions
- Data export, remote monitoring and calibration needs
Installation, Verification and Maintenance
Before installation
- Confirm electrical supply, water quality, drainage and ventilation.
- Reserve service clearance around the equipment.
- Keep the chamber away from uncontrolled heat, direct sunlight and strong vibration.
Routine control
- Clean the specimen area and water system according to the manual.
- Inspect lamps and rotate or replace them according to the configured system.
- Verify irradiance and temperature sensors at a frequency based on use, risk and quality procedures.
- Record maintenance, calibration and exposure interruptions.
DERUI provides a one-year whole-machine warranty, lifetime technical consultation, remote video guidance and operator training. Overseas installation can be arranged as a separately quoted service, and spare-parts support is available for up to ten years.
UV Accelerated Weathering Tester FAQs
What is the difference between UVA-340 and UVB-313 lamps?
UVA-340 is commonly selected when the goal is to reproduce the short-wave UV region of terrestrial sunlight. UVB-313 produces a harsher spectrum that includes short wavelengths not normally present at the earth’s surface. The applicable material method must determine the lamp; UVB-313 should not be selected simply to obtain faster damage.
Does ASTM G154 specify one standard test cycle?
No. ASTM G154 describes operating principles for fluorescent UV lamp and water apparatus and lists exposure procedures, but it does not identify one cycle as suitable for every material. Use it with the material specification or customer method that defines exposure and evaluation conditions.
Is ISO 4892 the correct standard for this equipment?
The precise fluorescent-UV reference for plastics is ISO 4892-3. ISO 4892-1 provides general guidance. Fluorescent UV exposure of paints and coatings is addressed by ISO 16474-3. Confirm the material-specific part before programming the chamber.
Can test hours be converted into years of outdoor exposure?
Not by a universal conversion factor. Correlation depends on the material, location, orientation, spectral distribution, moisture cycle, temperature and failure criterion. Use accelerated exposure for comparison and qualification unless a product-specific correlation study supports service-life prediction.
Does the chamber control relative humidity?
Fluorescent UV weathering tests commonly use a condensation function to create surface wetness rather than controlling chamber relative humidity like a temperature-humidity chamber. If a procedure requires a specific RH condition, send the method to DERUI for a configuration review.
What water should be used for condensation or spray?
Water quality affects deposits, nozzles and repeatability. Follow the equipment manual and applicable method, and provide the laboratory water specification during configuration so filtration or treatment requirements can be confirmed.
What should be included in an RFQ?
Send the test standard, lamp type, cycle, irradiance, specimen dimensions and quantity, holder requirements, water-spray need, data functions, laboratory voltage and destination country. DERUI can then confirm the appropriate chamber configuration.
Request a UV Weathering Tester Configuration
Send your material, specimen size, applicable method, lamp requirement and exposure cycle. DERUI will review the test profile and recommend the chamber, specimen holders, control functions and laboratory utilities required for the program.
- Standard and customized configurations
- Destination voltage and controller-language options
- Remote technical guidance and operator training
- Factory testing and documentation before shipment
