How dark is your darkroom? Radiography that uses intensifying screens is very susceptible to fogging from extraneous light. Improper safelights and light sources inside and outside of the darkroom can compromise the quality of your radiographs by reducing contrast and varying film densities. Unless your facility performs fog testing as part of a quality control program you cannot be certain that your darkroom is adequate. Facilities that provide mammography are required to perform fog tests semi-annually but other facilities should consider testing for fog to ensure the integrity of the darkroom.