During the windstorm yesterday, the PCal team attempted to complete end station calibrations of both ends.  The calibration for EY went off without a hitch (results to come in a separate aLog).  However, while setting up for the EX calibration, I dropped the working standard from the top of the PCal pylon onto the floor of the VEA.  The working standard assembly ended up in 3 pieces: the integrating sphere, one spacer piece, and the PD with the second spacer piece.  Minor damage was noted, mostly to the flanges of the integrating sphere and spacer pieces where the force of the fall had pulled the set screws through the thin mating flanges.  I cleaned up and reassembled the working standard assembly and completed the end station calibration.  Worried that some internal damage had occurred to the PD or integrating sphere, I immediately did a ratios measurement in the PCal lab.  The results of this showed that the calibration of the working standard had changed by ~2% which is at the edge of our acceptable error.  As a result of this accident, we are currently working to put together a new working standard assembly from PCal spares.  Unfortunately this means that we will lose the calibration history of this working standard and will start fresh with a new standard.  We plan to do frequent (~daily) ratios measurements of the new working standard in the PCal lab in order to establish a new calibration trend before the beginning of O2.