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Alodine 1200s+distilled water used for aircraft cleaning

July 10, 2009

I was recalled for duty when a fire broke out in an aircraft hangar.

Upon my investigations, it was discovered that Alodine 1200s+distilled water was used for aircraft cleaning purposes.

What could have gone wrong that fire took place while doing this procedures?

Could it be because of incorrect proportion mixture or because of too long an exposure?

Thank you.

Appreciate your reply.

Regards,
JaMil

Mohd Jamil Bin Abdul Majid
Fire Support Service - Singapore

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First of two simultaneous responses --

This is my opinion.
Virtually could not happen. A tiny possibility is that a very small amount of water got on the dry 1200. The heat of solution of this material is mildly exothermic, but hardly to the point of generating enough heat to cause combustion.
An example of extreme heat generation is dropping 1 pound of lye beads in the bottom of a plastic 1 gal bucket of water. It will probably melt the bottom out of the bucket.

1200 contains chromic acid which is an oxidizer. IF you got an organic like a light oil on the dry material, I would expect combustion.

If the 1200 was in solution, I can not think of anything that you could put in contact with it that would cause a fire.

James Watts
- Navarre, Florida
July 13, 2009

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Second of two simultaneous responses --

Alodine 1200S in solution, as normally used on aluminium parts, is aqueous and so is not flammable.

Was there a solvent used for cleaning prior to application of the Alodine? acetone ⇦this on eBay or Amazon [affil links] Warning! highly Flammable! , MEK / methyl ethyl ketone, isopropyl alcohol ⇦this on eBay or Amazon [affil links] and the ilk, commonly used for swab cleaning are all very highly flammable, but even then without an ignition source there cannot be a fire.

First thing you need to do is find potential ignition sources and either include them as potential causes or eliminate them if they are not relevant.

Brian Terry
Aerospace - Yeovil, Somerset, UK
July 14, 2009