MIL-STD-810 Salt Fog Testing

MIL-STD 810, Method 509 Salt Fog Testing is performed to evaluate the effectiveness of protective coatings and finishes on materials, ingress of moisture into connectors and sealed components.  Salt Fog Testing does not correlate to field life, but it provides an indication of potential problem areas associated with exposure to the salt (marine) environment.  The latest revision is Method 509.7 from MIL-STD-810H.

Ensuring Durability with Comprehensive Corrosion Testing

Salt is one of the most pervasive substances in the world, found in oceans, the atmosphere, ground surfaces, lakes, and rivers. It is impossible to avoid. Performing corrosion testing to exacting standards is crucial for product durability. Exposure to a salt corrosive atmosphere can lead to several detrimental effects, including:

Corrosion Effects

  • Corrosion due to electrochemical reaction
  • Accelerated stress corrosion
  • Formation of acidic/alkaline solutions following salt ionization in water

Electrical Effects

  • Impairment of electrical material due to salt deposits
  • Production of conductive coatings
  • Corrosion of insulating materials and metals

Physical Effects

  • Clogging or binding of moving parts of mechanical components and assemblies
  • Blistering of paint because of electrolysis

MIL-STD-810 Salt Fog Testing Procedures

MIL-STD-810 Salt Fog Testing is performed in a specially constructed chamber.  DES has one of the leading brands of a salt fog testing chambers.  MIL-STD-810 requires a 5% (±1%) by weight salt solution dissolved in water with a pH between 6.5 to 7.2.  The salt solution is atomized into the chamber as a fine wet salt fog or mist while the air temperature in the chamber is maintained at 35 ±2 °C (95 ±3.6 °F).   Two collection receptacles are placed inside of the chamber to measure the salt fog fallout rate.  The fallout rate is required to be 1 to 3 ml per hour for each 80 cm2 of horizontal collecting area. 

Test samples should be configured and oriented as they would normally be stored, shipped, or used.  The recommended duration is 48 hours of salt fog exposure followed by 48 hours of drying in ambient air with less than 50% humidity.  An alternating 24 hour test cycle (24 fog, 24 drying, 24 fog, 24 drying) has proven to be more destructive and is the way the MIL-STD-810 Salt Fog Test is most commonly run.  After the test, the samples are inspected for physical, electrical and corrosion effects.

Choose DES for Unmatched Salt Fog Testing Expertise

Choosing DES for your salt fog testing needs ensures:

  • Accredited Lab: DES is an accredited MIL-STD-810 test lab.
  • Experience: We have performed numerous MIL-STD-810 salt fog tests.
  • State-of-the-Art Equipment: DES has advanced salt fog testing equipment.
  • Precision: We possess the required calibrated support instruments to accurately measure the pH and salt solutions required in MIL-STD-810.

Contact us today to discuss your MIL-STD-810 testing project with one of our engineers. 

Share This:

Salt Fog or Salt Spray Testing

Salt fog (aka salt atmosphere or salt spray) testing exposes components to a fine salt fog mist that can result in rusting or corrosion of susceptible materials.  Samples to be tested are hung or placed on a rack inside of the salt fog chamber at the orientation that is specified in the applicable test method or otherwise agreed to with the customer.  The orientation during testing is important as unintended corrosion can result if the salt fog is allowed to condense and pool on the sample.  The samples are then exposed to a salt fog of defined salt content.  The salt solution used to provide the salt fog mist is usually a 5 percent by weight NaCl solution with the pH adjusted close to 7.0.  The salt fog condensate rate is monitored during the test to verify that the test requirements are met.

Continue reading Salt Fog or Salt Spray Testing

Share This: