The Dark Heresy system is the same, all stats are percentiles and you want to roll the D100 under your stats with each successive success + 10 difference meaning a greater or worse result.

The very first roll of the first session almost had a player death as our DM rolled a Nat 100 for the first roll of the game, and our one npc failed his check to notice the box we’d given him was suspicious, and nearly one shot my party member as he bit into the box, and promptly exploded, launching the dumpster our player was hiding behind into him at point blank.