ISO 17752:2012

Overview

ISO 17752:2012 - "Corrosion of metals and alloys - Procedures to determine and estimate runoff rates of metals from materials as a result of atmospheric corrosion" specifies standardized procedures to determine and estimate runoff rates of metals from metals, alloys and coatings exposed in the open air. The standard covers field-based runoff testing-continuous collection of rain/runoff water from exposed specimens-to quantify metal release rates to precipitation under real atmospheric conditions. It defines specimen preparation, exposure frames, site selection and characterization, sampling, evaluation and reporting requirements.

Key topics and technical requirements

• Test methods: Normative procedures for direct determination (field exposure with continuous runoff collection) and informative guidance for estimation based on application conditions.
• Specimen requirements:
  • Minimum flat-sheet specimen size: 100 mm × 300 mm (≥ 300 cm²); useful thickness 1–3 mm.
  • Surfaces should represent real products; avoid abrasion and fingerprints; degreasing (acetone/isopropyl alcohol) recommended.
  • Back sides to be sealed (adhesive tape) and cut edges sealed with metal-free lacquer or wax.
  • Single specimen acceptable if area ≥ 300 cm².
• Exposure frames and mounting:
  • Frames must not influence corrosion/runoff; specimens typically exposed at 45° from horizontal.
  • Minimum frame height ≥ 0.5 m to avoid splash or burial.
  • An inert blank holder should be exposed in parallel to collect background deposition.
• Site characterization and environmental monitoring:
  • Characterize site corrosivity using ISO 9226 standard specimens and measure environmental parameters: temperature, relative humidity, precipitation amount, precipitation pH, SO2 concentration/deposition, and Cl deposition (marine sites).
• Operational procedures:
  • Guidance on test duration, periodic collection of runoff samples, and evaluation of results (including record-keeping of volumes, pH, and total metal concentrations).
• Specimen handling and documentation: Identification, storage (≤ 1 week recommended between prep and exposure; storage RH ≤ 50%), photographic records and detailed specimen data (composition, surface finish, coating details).

Applications and users

ISO 17752 is used to:

• Assess metal release to the environment from building materials, coated products and metal structures.
• Support material selection, coating development and durability testing.
• Provide data for environmental impact assessments, regulatory compliance and lifecycle analyses related to metal runoff. Typical users: corrosion engineers, environmental scientists, coating manufacturers, construction and infrastructure designers, test laboratories, and regulatory bodies.

Related standards

Commonly used alongside:

• ISO 9226 (corrosivity evaluation)
• ISO 9225 (environmental parameter measurement)
• ISO 8565 (atmospheric corrosion testing requirements)
• ISO 4543 (corrosion tests for coatings)
• ISO 4221, ISO 4226, ISO 9169 (air/measurement methods)

Keywords: ISO 17752, runoff rates, atmospheric corrosion, metal release rate, corrosion testing, rainwater collection, test site characterization.