Our pH Color charts were developed using NIST-traceable pH buffers at 25°C. Colorimetric pH test strips do not offer “temperature compensation.” Care should be used when comparing results using test strips to those obtained with [...]
The Universal pH test paper does undergo some sublimation over time. This is evidenced by the slight discoloration of the color chart and vial. We have found that this sublimation does not normally adversely affect [...]
Typically, only two of the three pads changes color at any given pH level, which you match with the closest three blocks on the color chart. Changes can be subtle, and the colors may appear [...]
The pH test strips and papers are based on acidobasic indicators, which change their colors in a particular pH range. Acidobasic indicators are generally very stable compounds, and we have chosen the best indicators based [...]
When testing RO, distilled, or tap water, the strips may not behave like you would expect. The colors on the chart were developed for these strips using buffer solutions. The indicators used with the strips [...]
Currently, our pH test strips are designed for testing buffered solutions, and the calibrations (color charts) are made on buffers against a pH-meter measurement. For non- or low-buffered solutions, these strips are not suitable. For [...]