On 3/31/2012 6:47 AM, rader at hep_wisc.edu wrote:
Another thought: overcome the issue of how your eye sees green by comparing the dropchecker with actual known bromo blue solutions... make 5ml vials with stable pH ref. solns. + bromo. blue... e.g. 6.0, 6.4, 6.6 and 6.8 !?
This may not help the one in 10 males who have impaired color vision to some degree or another (depending on the severity and which colors are involved). For example, blues, purples, and even some pinks are indistinguishable for many with the most common forms of impaired color vision. If a test kit involves being able to distinguish from those colors, it's not going to work even with a reference. I suspect I'm not alone in having digital pH testers for just this reason.
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