Over the years, we have tried lots of diffent methods of trying to keep dust from blocking our view as we ride and race. We finally found Static Guard. Yup, that stuff that ladies spray on their skirts to eliminate clinging to their undergarments. We just spray on the inside and outside of the goggle lense, let dry, and then polish.
After the treatment with Static Guard, we drop Baby Oil on the foam on the top and side of the goggles. This is the same theory as putting oil on your air filter. The Baby Oil traps the small dust particles, keeping the dust from entering the inside of the goggles.
To clean the goggles, I simply fill the kitchen sink with warm soapy water, and submerge the goggles, swishing from side to side. Rinse with warm clear water, shake the excess water onto the ground, and let dry.
I have used this method in some pretty dusty events, and most of the time, never have to switch goggles when pitting. The fewer things we have to do during a pit the quicker we can get out. If we can get away with just quick dumping the gas, pits are less than 15 seconds.
Rick