I have no clue. Some material is more triggering for some than others. Most of what I post about in the mental health forums could be classified as triggering. It's not triggering for me, but is for so many others.

I had a pic of a person in pain at another site (I used it for an avatar) and one person pm'd me and said it was triggering them. It was something I didn't find triggering at all, but someone else did. So I guess we need to use discretion with everything we post.