For neutron detection and radioactive gas sensing, it is greatly beneficial to detect alpha (α) particles and gamma rays. In present work, continues passive radon detector (CPRD) has been constructed with native ZnS; Ag.Cl scintillator. The detector has been supplied with high efficient native nano particles scintillator for detection α particles. One of the features of this scintillator, the energy resolution is comparable with or even better than commercial ZnS(Ag) scintillator. This study provides an alternative for fabrication the native scintillator in absence of costly scintillator available in the market. Moreover, results of scintillation characteristics, along with physical properties of the scintillator are addressed and thoroughly discussed. For calibration, radon calibration system with dual radon monitor has been constructed in Najran University, Saudi Arabia. The experimental sensitivity of the passive CPRD cell for radon gas detection was constant with well know data already published in the literatures. Radon emission from natural sample has been measured by the fabricated CPRD cell.