This maybe a simple question, but  I can't see the answer in the books anywhere.

I am considering having an adversary who is a Untouchable and I can't find any rules about how psychic power affect them. I thought I read it in one of the 40K RPG books but as I have them all, I can't quite remember where to look.

According to the background the Untouchable has nothing at all to do with the warp nor any of a Librarians abilites will affect the Blunt, but do I just describe nothing happening at all or is there a rule about it?

Can a Untouchable shrug off an Avenger Blast? Will there be nothing if the Librarian does an Emperors Tarot reading on him? Can he be Cursed of the Raven-d?

Any ideas or advice?

WiseGuy said:

DH Radical Handbook

Psychic powers don't affect Untouchables.

They won't appear in divinations, or if they do it would be as a hole or void of some sort.

ItsUncertainWho said:

You're a star, thanks.

More, untouchables are psy null and have a aera efdfect also on psychic powers. Everybody within 5 m of the Untouchable is going to lose 5 psy rating, any effect in the zone will also suffer the same penality.

It is not rules but a conceptual vision how it work in the many books were blank are present from Jurgen the gunner in caïn storys to silence sister in Horus Heresy.

 I'd do Willpower bonus in meters as opposed to a flat 5 meters.

 WP bonus in Metres = penalty to Psy rating equal to the blanks WP bonus.
Blank is immune to all psychic powers and effects (with the exception of material objects that have been manipulated through telekinesis - a rhino dropped on your head is still a rhino!), warp shock, daemonic fear and auras etc.

If you delve into the lore however there are certain things that overload the blank, causing major damage or death.

That sounds a very fair rules concept. Whilst in my opinion being a blank isn't something that takes concentration, but naturally death of the Untouchable will end you of the problem and the interference.