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Tantalum capacitor burn out. toxicity issues

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neazoi

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Hi I have managed to burn out a 100uF 16v tantalum capacitor in the lab.
It made an explosion and then huge lot of red smoke started to appear, before I managed to switch off the PSU.
I opened the windows immediatelly and I tried not to breathe the stinky smoke.
After quite a few hout the room still has this burn smell, so I will leave that even more.

Now my consideration is about cleanning up the mess and toxicity.

As far as I read (https://en.wikipedia.org/wiki/Tantalum#Precautions) tantalum metal itself is biocompatible and used in implants.

Has anyone got a clue is aserious health risk arises by the chemicals of the tantalum caps?

For example, is that ok to clean up the smoke from the circuit and re-use that circuit or should I throw it away to avoid further contamination?
 

SunnySkyguy

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Most electrolytic caps, both solid and wet are carcinogenic when vaporized. Even epoxy and PCV fumes. Consider this. The chlorine gas from vaporized PVC cables on 3 Mile Island were more toxic than the radiation levels.

Wet mercury is not as toxic as dissolved in water and a vaporized thermometer can kill thousands in a closed room. but not easily done.

Consult MSDS from manufacturers process.
 

neazoi

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Most electrolytic caps, both solid and wet are carcinogenic when vaporized. Even epoxy and PCV fumes. Consider this. The chlorine gas from vaporized PVC cables on 3 Mile Island were more toxic than the radiation levels.

Wet mercury is not as toxic as dissolved in water and a vaporized thermometer can kill thousands in a closed room. but not easily done.

Consult MSDS from manufacturers process.

Ok the situation is this:

The capacitors are vishay ETPW6N107016K and the datasheet is here https://sklep.hfo.pl/upload/etpw.pdf

I accidentally connected one in reverse polarity and the capacitor exploded in the laboratory and then a very stinky red smoke came out of it.
The external body of the capacitor became black up to the middle. These capacitors have a protective fire resign, it may be that this resign burned out up to the middle. The capacitor itself did not explode apart, it was half black.
I avoided breathing the red smoke and I immediately opened up the windows, but the smell was there for more than two hours. I was not in there of course, but even so, I could barely smell the stink all over the rest of the house with the windows open.

Since I need to clean the laboratory I need to know the next things.

Are the materials used in such tantalum capacitors considerably toxic?
I find that tantalum is not highly toxic, but I do not know about the other materials.
As I said, I took precautions, I did not directly breathe the smoke in any means. It was just this smell afterwards.

I see some black smoke in the electronics nearby the failed tantalum capacitor, do you think this is toxic?
Please tell me if you know how to clear the bench area near the explosion, is it enough to use gloves and clean the bench using an ordinary house chemical cleaner?
Or do I need to do something else to avoid exposure for potential toxic materials?

A failed Hg lamp was hard to clean, but I do not think this situation with the capacitor is so toxic, since I did not directly breathe it.
Another time a small JFET failed and the resign stink like the capacitor, for a long time.
 
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SunnySkyguy

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AVX reports risk increases if inhaled or injested.

Fumes from burning components will vary in composition depending on the temperature, and should be considered to be hazardous, although fumes from a single component in a well ventilated area are unlikely to cause problems.
AVX


If you cough or have sore eyes or headache, these are bad signs. I would use traditional chinese medicine over western analytical approaches in this case, which works better for me unless critical. These herbologists know how to clean blood or plasma safer than pharmacutical Dr's. who usually cant tell. TCM works by boosting immunology.
TONY
- - - Updated - - -

Keep fresh air and sand in case of board fires in future. Epoxy has a definite bad odor and never breath in.

Joke in 1975 from RF Tech. Hmm smells like 100 Ohms.
 

betwixt

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Having worked in the test department of a factory producing items using probably several million tantalum caps and seeing hundreds explode, I can report that nobody died.
It's like most low concentation chemicals, thay are unnatural so should be treated as hazardous but they are not highly toxic. As long as you take reasonable precautions to avoid direct inhalation (sniffing the red smoke!) you should be OK. If the concentration had reached seriously dangerous levels you would be coughing violently or suffering eye/skin irritation and have breathing difficulty. I'm not saying the residue is safe, just that in relatively small quantities the danger is minimal.

Brian.
 
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    neazoi

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neazoi

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Having worked in the test department of a factory producing items using probably several million tantalum caps and seeing hundreds explode, I can report that nobody died.
It's like most low concentation chemicals, thay are unnatural so should be treated as hazardous but they are not highly toxic. As long as you take reasonable precautions to avoid direct inhalation (sniffing the red smoke!) you should be OK. If the concentration had reached seriously dangerous levels you would be coughing violently or suffering eye/skin irritation and have breathing difficulty. I'm not saying the residue is safe, just that in relatively small quantities the danger is minimal.

Brian.

Yes, no direct symptoms, no coughing violently or suffering eye/skin irritation. When the event happened, I imediatelly stop my breath and quickly opened the windows (had experience with previous stink from an exploded 2n7000 JFET). I really did not know that the smell of this smoke was, untill I went once more on the lab after a few minutes with the windows open, to see if this stink has dissapeared. It proved that it needed more than 10 hours with the windows open for this to dissapear. These resigns (and the JFET) really stink!
I would keep your point from your experience treating the remains ar hazarous, like any chemical, but not so freaked out, like the broken Hg lamp a few months ago. I hope, wearing gloves and throwing away the remaining blackened parts from the bench is enough for safety.

- - - Updated - - -

Just for reference, to anyone interested, I contacted Vishay, letting them know about the exact part number. Their reply was:

> the molding of the part is made by a thin layer of epoxy probably
> causing that bad smell.
>
> We are not aware of health issues created by one piece of a burned capacitor.
 

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