Cleaning soot from fire fighting camera cases - Anyone tried ?

[Fraser]

I have a fair number of thermal cameras that were used in Fire Fighting scenarios. This has resulted in them now having black soot engrained in their casings. All have been cleaned at the time of purchase using soapy water (washing-up liquid) but the engrained soot remains.

Of particular interest to me is people’s experience with cleaning solutions that can remove stubborn dirt, such a soot, without damaging the underlying material. In my case I am dealing with Radel R5100 used to make E2V/Avon Argus 4 cameras and battery packs. Radel is thankfully resistant to both weal Acids and strong Alkali’s.

In my basic research I have read that house fire related Soot can be a challenge to remove from plastic as it is often oily and contains many chemicals that can actually penetrate some plastics. This can make them impossible to remove but some cleaning methods can be quite effective. I am currently considering using a solution of Trisodium Phosphate that has a very Alkaline Ph of 12. TSP is a very effective cleaning agent that used to be found in many high performance cleaning solutions until environmental concerns caused it to be removed. It is still thought of as one of the best dirt, oil and grime removers available to the public. Interestingly, this highly effective cleaning agent may also be found in human food ! It is a Ph balancer.

https://en.wikipedia.org/wiki/Trisodium_phosphate

Has anyone else faced the challenge of removing engrained dirt, oil or soot from non shiny / textured plastic surfaces . If so, I would love to know what you used and how effective it was. Radel R5100 is thankfully a very robust material so I hope it can stand up to some serious chemical cleaning action 
I attach its data sheet.

Fraser

[Fraser]

A picture of two Argus 4 battery packs. One is new and the other has seen a lot of service in smoke filled environments. This is about the worst soot covered item I have as my cameras are nowhere near as engrained with soot.

Fraser

[RRtheone]

Hand washing maybe not a good way to remove these black soot. I have a Flir hard case that looks like this, and I used a combination of a drill, a cleaning sponge, and soapy water, which was quick and effective.

[Fraser]

For anyone interested is TSP as a cleaning agent, I attach a screen capture of a good summary of its abilities.

[themadhippy]

Id give bicarb cream and a toothbrush a try.

[jpanhalt]

2-butoxy ethanol ("Butyl Cellosolve" and several other names) plus a base such as ethanolamine are common ingredients in household cleaners, including strippers for acrylic floor wax. Diluted in water per label directions, it is safe on vinyl and many plastics.  The American brand I use is ZEP, but its active ingredient formulation is not unique.  I use it to remove soldering flux fro PCB/s.  It will remove many paints but does not seem to affect the silkscreen on PCB's.

While TSP will probably work too, it is restricted in some area.  Sodium metasilicate, which is also very alkaline, is sometimes used as a TSP substitute. 

If the cases have painted labels, be sure to test on them. (I am sure you know that.)

[helius]

TSP was never banned, it was just removed from consumer products (because it was making sewage too nutritious and encouraging algae growth). It's the main ingredient in Alconox precision cleaners.

[jpanhalt]

I know it's not banned, but it can still be difficult to find in consumer stores.  I have not seen Alconox at Home Depot (and other consumer stores) either.  I used that in a heated bath almost exclusively in the chemistry lab.  If Alconox didn't work for some organic goo, then it was dichromate/H2SO4, which is not recommended for plastics.

I forgot to add that using a light hydrocarbon solvent might be attractive, but they can have long-term adverse effects on plastics like hardening and crazing, which is probably much less likely with water-based cleaners. 

[gabiz_ro]

Maybe ultrasonic bath with some cleaning liquid will help due to cavity effect on textured surfaces.
Find best acting cleaning solution (liquid) and use it in ultrasonic bath.