The design, fabrication and testing of a prototype portable monitor of ultraviolet radiation hazards are described. This monitoring device conforms to a stringent spectral response curve peaking at 270nm with essentially no response to wavelengths above 325nm. The instrument uses a wideband interference filter system and a MOS photodiode to provide the desired spectral response. The device is capable of detecting flux levels at 270nm over five decades of watts per square centimeter. Also included is a suggested second generation design for a low cost, self contained Ultraviolet Hazard Monitor.