The data to back them up? The manuals that come with the mask clearly state "Warning: Clean only with plain water. Chemical cleaners (Windex, 409, Simple Green, etc.) contain alcohol and detergents which can WEAKEN the lens and goggle." That is what is known as a quote, not an assumption.
2nd truth and not an assumption, I have seen it personally. Not calling the service reps, not even looking at manuals, I have seen the results of these chemicals on polycarb and other plastic lenses. It wears them down. Will it break every pair, no. But getting on a web board and stating that "...alcohol...are all safe to use on lenses" (other cleaning methods in that statement, soap and water ommited from the quote because they can be safe). That is a false assumption.
Grace and Peace
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Current Project: THE ULTIMATE SHOOTPAINT BKO
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