Teflon-covered irradiance collectors should be cleaned with soap and water or alcohol—no stronger solvents—along with a soft cloth, tissue, or KimWipes. Do not use stiff brushes and do not use abrasives.
Regarding radiance windows, the window is quartz (not plexiglass) and can be cleaned with soap and water or alcohol. Again, do not use abrasives or stronger solvents.
Note also that quartz windows will stain if salt water drops are left to dry.