Atlas, a global leader in weathering and lightfastness testing, has published the Atlas EV Weathering Testing Guide, a new application resource designed to help electric vehicle development teams and testing laboratories evaluate the durability of exterior and interior materials under realistic environmental stress.

Source: Atlas

The guide brings together accelerated laboratory weathering, benchmark outdoor exposure, and practical guidance to support confidence in long-term material performance.

EV Durability Brings Higher Combined Stress Exposure
Electric vehicles use a wide range of materials and functional systems which face combined stresses that add up quickly. Prolonged solar radiation, high temperatures, moisture exposure, and repeated thermal cycling can all be in play at once. Interior surfaces behind window glass can reach temperatures exceeding 100° C on dark materials, while exterior parts are exposed to ultraviolet radiation, heat, dew, rain, and rapid temperature changes. Without application-appropriate validation, these combined stresses can lead to fading, warping, cracking, delamination, and functional degradation – affecting appearance, mechanical integrity, and long-term performance.

Supporting Earlier Validation Under Tight Development Timelines
OEMs, suppliers, and emerging EV manufacturers routinely face critical questions: Will exterior materials withstand worst-case outdoor exposure? Can interior materials tolerate sustained heat and sunlight behind glass? Are suppliers delivering components that meet durability requirements consistently across programs? Weathering testing helps material scientists answer these questions using standardized, reproducible methods.

Atlas Full-Spectrum Xenon-Arc Simulation for Interior and Exterior Parts
Atlas xenon-arc laboratory weathering simulates full-spectrum sunlight – including ultraviolet, visible, and infrared radiation. This full spectrum matters for colored materials that respond to visible light, and for materials sensitive to long-wavelength UVA, which can be underrepresented in fluorescent UV testing.

Source: Atlas

Atlas’ rotating rack instruments, the Ci Weather-Ometer^® and Xenotest^® systems, provide best in class uniformity for flat specimens used in critical material qualification work. The Atlas SUNTEST^® static horizontal systems, are perfect for three-dimensional parts, molded components, assemblies, and complex geometries that are difficult to mount in rotating racks.

Optical Filter Selection and Setup Consistency Influence Comparability
Daylight filter selection is a key determinant of exposure relevance, and window glass filters are used to simulate filtered sunlight conditions typical of interior testing behind glazing. Specimen mounting and backing can influence heating and moisture behavior. When setup details are not defined by the test standard, those variables can affect comparability between methods – and between labs. Atlas experts understand these factors. From technical advice to final test method implementation, Atlas provides the support that you need.

Source: Atlas

Benchmark Outdoor Exposure Supports Long-Term Confidence
Laboratory outcomes are often validated through natural weathering benchmarks. Atlas operates benchmark exposure sites in subtropical Miami and desert Phoenix, providing reference climates characterized by high UV levels, moisture-driven stress from overnight dew, and extreme heat.

These natural benchmark exposures are useful, especially for correlation studies and determination of acceleration factors. Natural test options include static exposure racks, glass-covered enclosures for interior simulation, and approximately five-times concentrated sunlight devices such as EMMAQUA^®. Newer approaches using ten “cool” mirrors expand testing capability for temperature-sensitive materials that cannot tolerate higher heat loads typical of traditional concentrated sunlight exposure. Equally important is Atlas’ unique Ultra‑Accelerated EMMA/EMMAQUA technology, which uses approximately ten‑times concentrated sunlight from twenty “cool” mirrors to deliver extremely high acceleration without overheating test specimens.

Correlating Accelerated Testing with Outdoor Results
Correlation studies connect accelerated laboratory exposure to natural weathering performance by comparing degradation trends and time-to-failure. Statistical measures, including Pearson correlation coefficients, can help teams evaluate whether laboratory parameters are reliably predicting outdoor behavior – and where refinement is needed when correlation is insufficient.

“Durability results can be difficult to compare if exposure conditions and setup details aren’t aligned,” said Dr. Oliver Rahäuser, Senior Product Manager at Atlas Material Testing Technology. “The guide highlights the parameters teams need to control and document, so results can be compared more reliably across methods, labs, and test partners.”