Automotive suppliers must navigate multiple international and OEM-specific corrosion test standards. The three most commonly referenced are ASTM B117 ISO 9227, and ASTM G85. Understanding the differences between these standards is essential for correct test specification and meaningful results.

ASTM B117 describes a neutral salt spray (fog) test using 5% sodium chloride solution at 35°C. It remains the baseline test for many general corrosion evaluations but is increasingly recognized as limited in its ability to predict real-world performance.

ISO 9227 provides similar neutral salt spray guidance with minor procedural differences and is widely used internationally, particularly in Europe and Asia. Like ASTM B117, it is a constant-condition test.

ASTM G85 introduces modified (cyclic) salt spray tests. Annexes within G85 cover various cyclic profiles that include salt spray, drying, and humidity or wet-bottom phases. These cyclic methods are particularly relevant for automotive exterior and underbody components where wet-dry cycles dominate.

For automotive suppliers, the choice of standard should align with the component’s service environment and customer requirements. Many OEMs now specify cyclic corrosion testing (ASTM G85 or equivalent) for body panels, chassis components, and fasteners, while retaining ASTM B117 or ISO 9227 for certain interior or less critical applications.

A versatile composite salt spray test chamber capable of running both constant and cyclic profiles provides the flexibility modern automotive test laboratories require.

pdreltest Composite Salt Spray Test Chambers are designed to comply with ASTM B117, ISO 9227, and ASTM G85, enabling suppliers to meet diverse customer specifications within a single equipment platform.