Responsible use of Morgan superwool (rockwool)

In brief, I am avoiding use of ceramic blankets after reading about health dangers. I am dealing with cancer issues, so Morgan superwool is my choice for a five minute riser in a rmh.  As have most folks.
Is this material a type of ceramic , or spun rock fibers?  Do the experts always use one inch  blankets inside a sacrificial pipe,
or sometimes blend the spun fibers in cob occasionally?   Am I shopping for the correct product? Examples attached

Rico, Morgan Superwool may be ok to use while not yet exposed to high temperatures, but using it as a riser is, in my opinion, not a great idea. It will be toxic once you have to remove it. keep it for the parts of the heater which are exposed to lower temperatures, and even then tread carefully (especially when dismantling: at least wet it and use a mouth mask). I prefer to see it as a carcogenic until fully proven otherwise.

I'll refer you to a post from Fox James:

https://permies.com/forums/posts/preList/95849/1344928

My understanding is that it becomes unsafe when directly exposed to the heat levels in a rocket stove riser.
I think best practice is to coat the inside rigidizer or refractory coating.

As far as I know Morgan super wool is Just a trade name for ceramic fibre?
If you are in a sunny or a dark room with a torch, as soon as you handle the stuff it becomes very obvious just how much it can pollute the air space with millions of air born particles.
I cant imaging that is good for anybody but these particles are said to be body soluble meaning they wont stay in your system
although I cant imaging they are good for you in any way!
Apparently the real danger comes when the product has been heated to high temp or exposed to naked flame, at this point the fibres become ‘non body soluble’ meaning they can stay inside your body potentially causing long term issues.
Even worst is the fibres can lay dormant in your body for years and then evolve into cancer!

Personally I started using ceramic fibre 20 odd years ago but only realised the real dangers about five years ago when I was diagnosed with kidney cancer in both kidneys.
The specialists consultants are highly superstitious as there is no family cancer history and although the fibres are more commonly related to lung cancer, it appears they could attack any body organ.
I have had one kidney totally removed and only 3/4 of the other kidney left with two remaining tumours.
So yes this is something everybody should  concerned about!

I was under the impression that Morgan Superwool is a spun basalt fiber, so it's not the same as ceramic from a chemical standpoint. I don't know whether it has the same sintering problem as ceramic fiber, but the precautionary principle is always the best way to roll when there's uncertainty and hazards involved.

It says on the box that it is made from an Alkaline Earth Silicate (AES) fiber I dont know exactly what that is  but, it has been much discussed on other forums and it is said to sinter at a lower temperature that ceramic fibre so in fact may be slightly more dangerous?

Alkaline earth silicate sounds like calcium silicate, magnesium silicate… heaven forbid beryllium silicate… I looked it up and calcium silicate seems likely. It sounds from others that all kinds of mineral fiber are nasty materials.

I wonder if there are other ways to achieve your goal—other materials, or perhaps an increased thickness of more traditional ones?

I think ceramic fiber insulation give the best performance out of anything available so far.
People who build forges use some costings which seem to be effective safety barriers.

Growing up in the 80''s I was expecting to have a power armor exoskeleton with a layer of space shuttle tiles by now.
I'd settle for the tiles at a reasonable price!

William Bronson wrote: I think ceramic fiber insulation give the best performance out of anything available so far.
People who build forges use some costings which seem to be effective safety barriers.

Growing up in the 80''s I was expecting to have a power armor exoskeleton with a layer of space shuttle tiles by now.
I'd settle for the tiles at a reasonable price!

You may want to watch this guy he does experimental coatings for furnace applications...

I will be using calcium silicate board to insulate the outside of my BBR core. It does not contain fibers, but of course you must still be careful with the silica. In my opinion, it is a viable alternative. It does not insulate as well as superwool, but you could go slightly thicker with it (e.g. 5 cm board instead of 2.5 cm blanket), or just accept that it will perform slightly less.
It's also not cost-prohivitive in my opinion.

https://www.broodoven.com/calcium-silicaatplaat-1000x500x50

Learn something new every day on Permies!  Thanks for all the information folks, knowledge gives us power.  Which is better than particulates giving us health problems
Fox, I am with you, and pray for your one kidney. I came out of surgery, chemo and radiation with a vastly different body and an enhanced will to live....having lost one kidney and all saliva glands in the bargain.  So these warnings and suggestions are taken to heart; I try my best to stay vertical on this verdant green planet.

Could superwool be put in a cob sandwich for a riser?  I envision cutting the blanket, then dunking it carefully into clay slip.  I could then slather cob around a wood riser form, add the superwool around that, and finish with another layer of cob. After firing the rocket to burn out the wood, I could inspect for any blanket that might be exposed.  Patch then with cob before the next firing.  Safe or another folly?

If this sounds plausible, I can give it a try.  
Alternatively,  I could just stick to cob, fire brick or refractory casting......?  Opinions and RMH proselytizing welcome!

One more question,  I pray you
Have any of you changed your methods of stove building, aside from Fox, with this realization of superwool toxicity?   I am thinking of Thomas and his shorty core build.... with lots of steel framing protected by superwool.   Should I just keep it out of the core, or abstain from using it altogether? Thanks for the help

Hi Rico;
Superwool only changes after heating above 1400F.
All the other location's you see Superwool being used are completely safe.

After a five minute riser has been in operation it should be handled carefully.
Wear a respirator if you own one or N-95 mask if you do not.
Do not bang it around if removing it from a core, do not stick your face  over it to look while moving.
I have installed, removed , installed on a different core many SW risers. Not one time did I receive a face full of dust.

The stove pipe it is built in is not sacrificial, they last for many years with no degradation.

If you build a quality core to specifications, there is no reason to even see the riser for many -many years.
They do not wear out, and there is no reason to open a bell to look at your riser unless your stove has a problem.

Heated Superwool is no more dangerous than fiberglass insulation is.
In my childhood I remember playing in attics with exposed fiberglass batts, every bit as bad as superwool and instead of an 8" x 48" tube it was a whole room.
Admittedly the hazards of fiberglass and asbestos were not widely understood  in 1965, if they had been our schools and public buildings would not have used them.

A five minute riser is the fastest, least costly way to build a riser.
A fireclay perlite riser is another low  cost alternative, but I would only use one under a barrel with a removable  lid, where the riser can be inspected for cracking.

If you want the Cadillac of risers then purchase 2300F + insulated firebricks, I recommend the  9 x 4.5 x 3" bricks as they are much more stable in a dry-stack riser.
After you build that IFB riser you should then wrap it with an insulating blanket, such as Superwool or perhaps if you like itchy's than rockwool will also work.

So in my opinion. if treated with common sense  (after high heating) Superwool is a safe alternative to expensive insulated bricks.





 

Now I see more of the big picture, thank you Thomas.  These concerns are riser concerns.  
Fireclay with perlite risers are looking better all the time.

Would it make sense to form one as a sandwich, the perlite mixture packed  between 10 inch stove pipe and a 6 inch sacrifice pipe in the perfect center? That way a good two inch cylinder could face the force of repeated firings?
Does anyone have a good ratio for mixing a robust clay/perlite riser, maybe 60/40?

Hey Rico,
You do not want to use any metal as sacrificial.  It rots apart and falls down into the riser, temporarily restricting it.
To build a fireclay/ perlite riser you use a concrete  soni tube  as sacrificial tube, it just burns up.
However, to much moisture in your mix will cause the tube to sag and deform the riser.
Pour the riser and fire the stove on the same day

Mix??? I don't remember it has been many years since I made one, lots of perlite and just enough fireclay for it all to stick together.

Yes, that inside pipe would be an awful idea.   Appreciate the heads up.  I don't know  much terminology, how can I say 'removed' in a  better way, um, a temporary steel/ductwork pipe? Sorry, I was considering a lightly greased 6 Inc pipe, maybe with wax paper gasket.  Then when mixture is half set, I could slowly pull the pipe out before firing?  I can try and let you know if it succeeds, is this possible to leave a smooth blemish free surface for the riser

Use a soni tube it leaves a perfect bore