While traversing through obstacles in the Flash Powder Factory you may come across Fallen rubble. Searching these may yield pieces of Rogue armour, flash powder, catalytic powder or sets of apparatus. It is also possible to find nothing at all. It is assumed receiving a piece of Rogue Armour is considerably rare.
The Fallen rubble only appears in the rooms with the Mixer Machine and the rooms with the Reagent Machine (A), as marked in the map below.