ISO 14993:2026

Overview

ISO 14993:2026-Corrosion of metals and alloys: Accelerated testing involving cyclic exposure to salt mist, dry, and wet conditions-is an international standard developed by ISO/TC 156. This standard specifies the apparatus and procedures needed to conduct laboratory accelerated corrosion tests for comparative quality evaluation of metallic materials in salt-contaminated outdoor environments. Unlike the classic neutral salt spray (NSS) test, this cyclical method more realistically simulates the alternating salt, dry, and humid conditions experienced by metals outdoors, leading to a better representation of real-world corrosion phenomena.

The standard is applicable to a broad range of metallic substrates and coatings, including:

• Metals and their alloys
• Metallic coatings (anodic and cathodic)
• Conversion coatings
• Anodic oxide coatings
• Organic coatings on metallic materials

Key Topics

• Test Apparatus and Equipment
  ISO 14993:2026 details requirements for corrosion-resistant apparatus, precise humidity and temperature controls, air saturators, and collection systems. Equipment must ensure even salt dispersion and simulate cyclic weather exposure.

• Test Solution
  The standard specifies a neutral sodium chloride (NaCl) solution with strict concentrations and purity requirements to avoid interference from contaminants.

• Exposure Cycles
  Specimens are subjected to repeated cycles including:

  • Salt mist spray (35°C)
  • Dry conditions (60°C, <30% RH)
  • Wet (humid) periods (50°C, >95% RH)

• Test Specimen Preparation and Arrangement
  Guidance is given on selecting, handling, and arranging specimens for fair and reproducible results, as well as edge protection and cleaning methods to maintain surface integrity.

• Evaluation of Results
  The standard outlines qualitative and quantitative methods for assessing corrosion, such as visual inspection, counting corrosion defects, measuring mass loss, or micrographic analysis.

• Test Reporting
  Comprehensive test report requirements ensure full traceability and repeatability, including all environmental conditions, sample specifications, deviations, and results.

Applications

ISO 14993:2026 delivers significant practical value across multiple industries:

• Automotive and Transportation: Evaluating corrosion protection for vehicle parts exposed to road salts and changing climates.
• Construction and Infrastructure: Testing building materials or coated metals used in coastal or salt-contaminated areas.
• Marine Engineering: Qualifying metals and coatings for components in ships, ports, and offshore structures.
• Manufacturing: Comparing new metallic materials or protective coating systems in product development and quality control.
• Paints and Coatings Industry: Assessing the performance of organic and inorganic coatings applied to metals.

This standard enables manufacturers, researchers, and end-users to benchmark materials for their resistance to corrosion under more realistic, cyclic outdoor exposure conditions, supporting durability claims and regulatory compliance.

Related Standards

ISO 14993:2026 complements or references several other key standards relevant to corrosion testing and performance assessment, including:

• ISO 11997-1: Cyclic corrosion tests including humidity and condensation, particularly for coatings with intentional scribe marks.
• ISO 1514: Paints and varnishes-Standard panels for testing.
• ISO 2808: Paints and varnishes-Determination of film thickness.
• ISO 8044: Corrosion of metals and alloys-Vocabulary.
• ISO 4623-2, ISO 8993, ISO 10289, and the ISO 4628 series: Standards for evaluation of corrosion defects and corrosion resistance in coated materials.

By adhering to ISO 14993:2026, organizations can ensure reliable, globally recognized testing methods for evaluating corrosion resistance of metals and their protective coatings in salt-laden, outdoor environments.