Question on TF-100 T/A test


LifeTime Supporter
May 21, 2007
Carrollton, TX
Instructions say to add the R-0009 reagent till the color changes from green to red, counting the drops. At some point the color changes from green to a pink/light pink. It usually takes around 2 more drops to fully change to a full red color. So do I count the drops between the pink color till the color actually reaches red to figure T/A or stop at the pale pink color?


TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
Silver Spring, MD
If you are unsure of the color change you keep adding drops until the color doesn't change any more and then you don't count the drop that failed to change the color. (There must be a better way to explain that.)