  We present surface pictures of the damaged electrodes from the Glass
Resistive Plate Chambers (GRPCs) taken by an Atomic Force Microscope (AFM). For
the test, a set of chambers were operated with freon mixed gas (damaged) and
freonless gas (not damaged), contaminated with 1000 to 2000 ppm of water vapor.
In the AFM pictures, clear differences in damage are seen between the
electrodes in the chambers with the freon mixed gas and the freonless gas; a
combination of freon and water vapor caused the damage.
