Two different things, I know.
Yesterday I was looking at some stuff here and noticed that they do this fuel additive.
I have many times heard that EGME (one trade name being “PRIST”) is highly toxic, but is used because you need to add only about 0.1%, whereas with IPA (which is non-toxic, and which is what I use) you should add around 1%.
On my last trip to Greece I carried 4 litres of IPA and that covered only the initial flights UK-Corsica, and then Greece-Zagreb and Zagreb-UK. The intermediate flights were done at lower levels, but had they been done at Eurocontrol levels I would have had to carry something like 10-15 litres of IPA!
If EGME (which is what the above stuff turns out to be)
is toxic, one is going to get exposed while pouring it into the tank during refuelling. The fuel man will also get exposed… Do you put on disposable gloves? What about inhalation?
The reason I use fuel anti-ice is not because avgas freezes (it doesn’t freeze until you get down to -58C) or because the TB20 has any reported susceptibility to fuel system icing, but because dodgy avgas (typically from bowsers which have been left standing at little-used airports over the winter) could contain water, and I have already had one “interesting moment” this year which I don’t want to see again.
TKS is the other one. This isn’t supposedly anywhere near as bad as EGME but still has something dodgy in it. What are the alternatives which work as well?
EGME toxicity is mostly chronic rather than acute – that is, those exposed to very small doses every day at the workplace are at a greater risk than casual users. The prevailing routes of exposure are either inhalation or skin absorption. It isn’t really volatile, so the inhalation route is out for your kind of use; dermal exposure will be reliably prevented by wearing compatible gloves (e.g. butyl rubber). Even if you do get a drop or two on your skin, for one-time exposure it’s less trouble than, say, battery acid.
TKS is 85-90% ethylene glycol, the rest is water and IPA. The only relevant toxicity is by ingestion, and LD50 is fairly high – on the order of 100 mL for an average human.
I use TKS and its also on the prop which covers the whole airplane with a mist. What about inhalation? I turn off all vents when I use it. But I figure some must still come in since its not pressurized.
Peter, I never used IPA or Prist in the Mirage due to the very low freezing point of Avgas. Never had a problem with -40s at FL250, would be surprised if you saw issues in the teens FLs.
I know that a plus point for the 525 series Citations is that they don’t need Prist whereas their predecessors in the 500 series did. At sim school this is taught as a big deal
With Jet fuel I bought pre-mixed with Prist in the US as they only have Jet-A. I don’t use it in Europe and never want to put it in by hand myself.
I never used IPA or Prist in the Mirage due to the very low freezing point of Avgas
At -58C, pure avgas is not the problem, ever. The problem is water in the avgas.
Take a PA46 to some little used airfield, in March, and fill up from the bowser, then climb to FL250 and see what happens. Then take the fuel you drained out of your tanks and spend £500 on a lab to get it tested 
I have not yet seen evidence that the TKS fluid has any nasty stuff in it. The one I use is from Silmid.
Peter, I wasn’t being glib. I flew the aircraft out of numerous remote airfields all year.
Read the MSDS (material safety data sheet) that comes with it. It is legally required for nasty chemicals. It will tell you precisely what safety precautions are required. Any UK organisation dealing with this will have it in place under COSHH. Turns out all that elfin’ safety stuff does have a use.
My TKS came in a 20 litre drum, yellow, metal, with I believe “Shell” on it, from Silmid, about 10 years ago. I see they no longer sell what appears to be the same stuff but they do the Kilfrost brand; data sheet here (you have to manually rename the downloaded file to have a .pdf suffix – great piece of web design ). I have asked them for the MSDS.
In fact Silmid don’t seem to do anything specifically for TKS systems – unless I am missing something.
