A versatile boiling water and superheated steam facility has been developed for out-of-pile corrosion testing of materials that are being used and considered for application in boiling water reactor (BWR) and superheat reactor (SHR) systems. The following capabilities have been achieved: 1. Simulation of the various environments (other than irradiation) that would contact materials in a Dresden type BWR and an SHR utilizing steam generated therefrom. Test space is available at 1000 psi in saturated steam, steam-water mixture and saturated water at 546°F and in superheated steam at 1050°F. 2. Dynamic fuel-cladding material tests operated with a heat flux of 250,000 Btu/hr-ft2 for testing tubular type cladding under representative BWR heat transfer conditions. 3. Dynamic fuel-cladding-material tests operated with a heat flux of 170,000 Btu/hr-ft2 for testing tubular cladding under representative SHR heat-transfer conditions. 4. Control of oxygen and hydrogen content in the steam and water to simulate the gas conditions from radiolytic water decomposition found in a BWR. 5. Attainment of metal temperatures of 1300°F while superheating steam to 1050°F.