MIL-STD-810 Test Method 508.6 – Fungus
- Tests for fungus contamination
- Single procedure with two failure modes:
- Feeding the spores and changing the material properties
- Spores excreting material that changes the packaging properties
- Can do the test or use decontamination measures
About MIL-STD-810 Method 508
There are a couple of ways to do fungus testing. The test described here only has one procedure in it, which is different from many of the other MIL-STD-810 testing methods.
The procedure entails subjecting the materials you’re putting together in an electronics package to spores of different types of fungi since complications can arise from different strains of fungi. You’re looking for the breakdown of the materials due to it either being nutrient to (“feeding”) the spores or the excretions from the spores being acidic, which change the material properties. This test is done under high temperature and high humidity to simulate jungle-like conditions.
Fungus can be a major problem for electronics. This is why a long time ago paper wrap capacitors or cellulose were used in certain types of circuit boards. However, almost everything is now compliant with being non-fungus nutrient.
One case where the industry really hasn’t changed is PBC. This is one place where you have to do something special, like using conformal coating to isolate components from nutrient growth, to ensure units pass MIL-STD-810 508. In total, the test takes 28 days to complete.
If it’s not in your schedule or in your budget to test for fungus, you can also do analysis or qual by analysis. This requires you to access a database where you can look up each and every part in your system and just verify that they are non-nutrient supporting.
A standard approach to decontaminating units after they’ve been exposed to fungi is with a common soap and hot water solution or disinfectant, like Lysol.