Dräger Tube Formic Acid 1/a (10)PN: 6722701 Dräger-Tubes™ are used together with a Dräger tube pump for measurements of gases, vapors and aerosols, usually in air, and are one of the classic methods of gas analysis. This Dräger-Tube is used for the detection of formic acid and has the following standard measuring range: 1-15 ppm Measurements: 10 Application Range Standard Measuring Range: 1 to 15 ppm Number of Strokes n: 20 Time for Measurement: approx. 3 min Standard Deviation: ± 10 to 15 % Color Change: blue violet ä yellow Ambient Operating Conditions Temperature: 10 to 50 °C Absolute Humidity: Reaction Principle HCOOH pH indicator ä yellow reaction product Cross Sensitivity It is impossible to measure formic acid in the presence of other acids. Organic acids are indicated by the same color change, but partly with different sensitivity. Mineral acids, e.g. hydrochloric acid are indicated with different sensitivity and by red color