Magnesium oxysulfate cleanroom panels and silicate panels are both marketed as A1 non-combustible inorganic sandwich walls for cleanrooms, hospitals and food plants. On paper they look interchangeable. In the field they are not. One is a rigid MgO-MgSO₄ cement board, the other a calcium silicate or potassium silicate board. That single formulation difference decides chloride risk, moisture stability, screw-hold strength, machinability, cost and which GMP or fire-compartment project the wall can actually pass. This module gives procurement engineers, cleanroom GCs, fire-protection subcontractors and project specifiers a side-by-side comparative evaluation before RFQ release, anchored by SAMZOON Foshan source manufacturing, free pre-bid samples and South China purification project QC.