The material storage (資材庫,Shizai-ko?) is an area of Incineration Disposal Plant P-12A 1F featured in Resident Evil 3: Nemesis.
Two packs of Grenade Rounds can be obtained here. There is the locker in the end of the room. Using the plastic card of the Facility Key with ultraviolet barcode opens the locker and the Rocket Launcher can be collected there.
Checking the Card slot
It is closed with a sturdy-looking door. There's a tiny slot where a plastic card could fit.