ISO 5156:2022

Overview

ISO 5156:2022 - "Corrosion of metals and alloys - Corrosion test method for disinfectant - Total immersion method" specifies a standardized laboratory method to determine the corrosivity of disinfectants against metals and alloys under total immersion conditions. The document defines required apparatus, specimen preparation, conditioning, test procedure, and the information to include in a test report. It does not cover other corrosion test methods or the interpretation/evaluation of results, and users must ensure appropriate safety and regulatory compliance.

Key topics and technical requirements

• Scope and limitations
  • Applies only to total immersion testing of disinfectants on metal materials.
  • Does not include evaluation of corrosion test results or other test methods.
• Apparatus
  • Test cell (wide-mouth sealable glass jar or pressure-resistant vessel), specimen supports, analytical balance (0.1 mg precision), constant-temperature device, evaporation-preventing device, digital microscope (1x–100x, ≥3 MP), oven ((38 ± 3) °C to (120 ± 3) °C), vernier caliper (±0.02 mm).
• Reagents and materials
  • Acetone conforming to ISO 6353-2, waterproof abrasive paper (#120) per ISO 8486-1, grade 3 water per ISO 3696.
• Specimens and preparation
  • Typical specimen size: 50 × 25 × 2 mm with a 3 mm mounting hole; polish, mark, preclean (acetone, drying), and weigh to 0.1 mg.
• Conditioning and test parameters
  • Metal immersion area to solution volume ratio: 1 cm² : 10 ml.
  • Test solutions: concentrated (as received) and recommended use dilution.
  • Typical test temperature: (38 ± 3) °C; common exposure time: 168 h (24 h optionally).
• Procedure and measurements
  • Triplicate specimens per condition plus reagent blanks and a reference specimen.
  • Post‑exposure rinse, acetone ultrasonic cleaning, drying, weigh, and visual inspection for discoloration, etching, accretions, pitting.
  • Remove corrosion products per ISO 8407, calculate weight loss and corrosion rate (formula provided), evaluate pitting with a digital microscope or ISO 11463.
• Test report
  • Must include full descriptions of metals/alloys, disinfectant, equipment, deviations, results and calculation references, test date, and standards used.

Applications - Who uses ISO 5156:2022

• Materials and corrosion engineers evaluating disinfectant compatibility with metal components.
• Quality control laboratories in healthcare, aerospace, food processing, manufacturing and maintenance that use disinfectants.
• Product developers and safety teams assessing material selection for equipment exposed to cleaning/disinfecting agents.
• Test laboratories seeking ISO-compliant methods for disinfectant corrosion testing.

Related standards

• ISO 3696 (water for analytical use), ISO 6353-2 (acetone), ISO 8044 (corrosion vocabulary), ISO 8407 (removal of corrosion products), ISO 11463 (pitting corrosion evaluation), ISO 8486-1 (abrasive paper). References include ASTM F483 and ST/SG/AC guidance for evaporation prevention.

Keywords: ISO 5156:2022, corrosion test method, disinfectant corrosion, total immersion, corrosion of metals, pitting corrosion, corrosion rate, corrosion testing standards.