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Heresite’s New P-413 Becomes First HVAC-R Coil/Radiator Coating to Meet ISO 12944-9 (formerly ISO 20340) Standard

Offshore paint qualification standard approximates real-world environmental conditions

Manitowoc, Wis. (June 23, 2017) – Heresite, a leader in the development of thin film corrosion resistant coatings, has successfully met the demanding requirements of ISO 20340 – regarded as a key corrosion standard for performance coating systems destined for offshore structures, the most severe marine/salt air environment.  The ISO 20340 test for C5-M environments cycles the coating between salt spray, UV radiation, and temperature shocks for 25 weeks (4,200 hours).


The ISO 20340 test results demonstrated that after 4,200 hours (25 test cycles) no external damage of the P-413 coated layer was observed and the scribed areas did not show any delamination or corrosion infiltration.  This result was consistent both with and without a UV resistant topcoat (Heresite’s UC-5500).


“While the static ASTM B-117 salt spray remains a widely utilized screening tool, customers are increasingly searching for coatings that perform well in cyclic testing that more closely approximates real world conditions,” stated Peter Hellman, General Manager for Heresite Protective Coatings.  “For this reason, Heresite developed and tested the NEW P-413 coating against ISO 20340, as well as the more traditional static salt spray tests used by our competitors. We’re extremely pleased that P-413 demonstrated greater flexibility as well as greater corrosion, chemical, and temperature resistance in all tests.”


About ISO environmental corrosion testing

The International Organization for Standardization (ISO) is well known for developing criteria for assessing local environment corrosion severity as well as tests to pre-qualify coating systems for those different environments.  According to its environmental classification system (ISO 9223), the most severe marine environment is C5-M. A C5-M environment is one in which coatings will be subjected to high humidity, sea water spray/heavy chloride deposition rates and intense UV exposure throughout their lifespan.


About Heresite Protective Coatings

Established in 1935, Heresite Protective Coatings has spent more than 80 years developing and perfecting protective coatings that solve corrosion problems in a variety of applications including commercial heating, cooling, refrigeration or other industrial process coils, as well as components that are regularly exposed to corrosive conditions, including coastal and marine environments. The company’s ongoing focus on technology leadership, rigorous quality and process control, and customer satisfaction has led to the development of multiple industry-leading coatings based on phenolic, epoxy phenolic, urethane and silicone chemistries. Heresite coatings not only provide protection in corrosive high salinity marine conditions, but industrial applications such as wastewater treatment, swimming pools, food processing, mining, oil and gas, semi-conductor production, pulp and paper, textile factories and other environments where these systems are exposed to chemical fumes. For more information visit or call 800-558-7747.