Modules used:

*Moder8 6.x-1.3

I need to be able to let users of specific roles moderate specific content but not all content. To clarify this a bit better, I have the following roles;

article contributor: users with permissions to create articles
article moderator: users with permissions to moderate those articles

event contributor: users with permissions to create events
event moderator: users with permissions to moderate those events

When articles and events are created and send for moderation, both roles i.e article moderator, and event moderator are able to moderate articles too.
What I want is to stop them from approving articles etc.

Please let me know if more info is needed.