EMB145 Captain reports that a white haze forms on the smoke masks of all the company aircraft equipped with the Puritan mask. This haze forms in a couple of days and requires regular maintenance which is not being done.

Narrative

During the cruise portion of the flight the First Officer requested to use the restroom. I began (altitude above 25;000 FT) to deploy my mask and noticed that the lenses were obscured by some type of white haze. The haze was so bad it was impossible to see through the lenses of the smoke goggles. I attempted to clean the goggle with water and a napkin and was able after a minute or two to remove some of the haze. This has been an ongoing problem with the aircraft that come equipped with the Puritan smoke mask. I have completed safety forms and spoke with management and maintenance on several occasions. I have even provided pictures of mask with this obscuration. The last time I brought it up I was assured it would be taken care of. This continues to occur because of a lack of preventive maintenance. If there was ever an event that required relying on one of these obscured masks in a smoke type emergency; I believe that the outcome wouldn't be good. These masks need to be checked by maintenance on a regular basis with the Mechanic doing the inspection recording it in the log book.