Ferrosilicon

Safety First! Precautions/procedures and equipment.

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Tyvole
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Ferrosilicon

Post by Tyvole »

Just been reading the MSDS for ferrosilicon, such as you might use in a hot prime if I'm not mistaken. Apparently under thermal decomposition in the presence of water it generates arsine, phosphine and hydrogen! :o
I worked in the semiconductor industry for a while, where arsine and phosphine are used in some processes. Those gases are seriously evil - extremely toxic and pyrophoric nasties. If you can smell garlic or fish, it's probably too late to worry about it.
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Aardvark
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Re: Ferrosilicon

Post by Aardvark »

Scary stuff mate! Good job we have a group of people with some know-how about them here! Me not included of course..

Sam.
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richardh08
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Re: Ferrosilicon

Post by richardh08 »

Arsine - AsH3
Phosphine - PH3

Where do the arsenic and phosphorus come from?

Are they impurities in the ferrosilicon? If so, then I would imagine the amounts involved would be very small, especially in the quantity of ferrosilicon that is typically included in a pyro composition.

Having said that, as someone who once suffered from a very mild case of cyanide poisoning, I still wouldn't want to be around if they are being generated in any quantity whatsoever.
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Tyvole
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Re: Ferrosilicon

Post by Tyvole »

I don't know where the As and P come from, I was just astonished to read it in the MSDS. What I do know is that the LD50 for these gases is around 0.3 - 0.5 ppm, which isn't much. There's not really any need for panic though, unless you're in the peculiar habit of sniffing your stars while testing them in the bathroom. :-)
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Niall
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Re: Ferrosilicon

Post by Niall »

Are you saying I should stop sniffing stars in the bathroom? Can we be clearer here folks?
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Aardvark
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Re: Ferrosilicon

Post by Aardvark »

Bugger! That's the best part :(
Tyvole
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Re: Ferrosilicon

Post by Tyvole »

Niall wrote:Are you saying I should stop sniffing stars in the bathroom? Can we be clearer here folks?
Only if you've used a ferrosilicon hot prime..... I guess. Otherwise, well, who am I to say?
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Nightsun
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Re: Ferrosilicon

Post by Nightsun »

Has anyone ever had a reaction on the skin from KNO3? Even using it outside causes intensely itchy lumpy and very angry welts to form on my ankles. After a bath and an application of Boots topical steroid cream and an hour it's gone ( the rash, not my ankle ) just would like to know if anyone else has had that.
' I regard the earth as a courageous global experiment that failed ' QUENTIN CRISP
Tyvole
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Re: Ferrosilicon

Post by Tyvole »

Sounds a bit as if you have been sensitized by something. Exposure to some chemicals/substances, such as Hexamine for example, can do that. Have you always worn gloves etc. when mixing? I mean, always?
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Nightsun
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Re: Ferrosilicon

Post by Nightsun »

Yes, always used gloves and industry grade dust mask. It's just KNO3 and now even with minimum use I take a bath right after and that seems to stop that. Just shows what can happen though. A fellow pyro got contact dermatitis from dichromate.
' I regard the earth as a courageous global experiment that failed ' QUENTIN CRISP
Tyvole
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Re: Ferrosilicon

Post by Tyvole »

Words to the wise there from Nightsun. Never compromise your personal safety for this hobby. We deal with nasty stuff that demands our respect. Even given that, it can play dirty tricks - take nothing for granted! Stay safe.
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Niall
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Re: Ferrosilicon

Post by Niall »

Try Piroteze or similar too, can sometimes help the body calm down to these reactions.
All wretch and no vomit.......
starseeker
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Re: Ferrosilicon

Post by starseeker »

Nightsun wrote:. A fellow pyro got contact dermatitis from dichromate.
With dichromate being a carcinogen i would have thought if he was using without suitable precautions ,that dermatitis would be the least of his worrys.

I must say that this is one chemical that i will not use,it worrys me to much.
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Pyro-Gear
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Re: Ferrosilicon

Post by Pyro-Gear »

I have 50grms of dichromate I have had it for 6 years I still have 50grms left :|
starseeker
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Re: Ferrosilicon

Post by starseeker »

If you need to passivate Mg,i just use boiled linseed oil,
i know it is a much slower process but far less worries.
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