Warning!
I thought I try Olia very light ash, since it doesn't have Ammoniak. Let me tell you that even though it doesn't have and claims to work with oils the damage it does to your hair is equally bad. Even worse, I never ever responded allergic to a hair dye before, but with Olia I did and it was bad, I even had low grade fever and numbing of the cheeks. A week on now, I finally start to feel somewhat better. Pity, the color was quite okay.
Be careful, just because a hair dye claims to have no ammoniak doesn't mean it's better for you. I had to learn it the hard way.