Phosphoric Acid Esters Detection Tubes 0.05/a (0.05 ppm)
For short-term measurements more than 160 Draeger Tubes are available to measure the so called spot concentrations of specific gases.
A wide range of different gases and vapors can be detected and measured, such as:
- Determining and measuring concentration peaks
- Measuring personal exposure in the inhalation area
- Detecting leaks in pipelines, gas installations etc.
- Air analysis in sewers, shafts and confined spaces
|Standard Measuring Range:
||0.05 ppm Dichlorvos
|Number of Strokes (n):
|Time for Measurement:
||app. 5 min
||yellow -> red
||10 to 40 ° C
||3 to 18 mg H2O / L
||a) (CH3O)2PO2-CH=CCl2 + Cholinesterase ─> inactive enzyme
b) Butyrylcholine iodide + H2O ─> Butyric acid
c) Butyric acid + Phenol red ─> yellow reaction product
If phosphoric acid esters are present the enzyme is inactivated and butyric acid will not form, thus the weak alkali solution colors the indicating layer red and must be stable for 1min. If the enzyme remains active, phosphoric acid esters are not present, and the indicating layer remains yellow because of butyric acid formation.
||Other phosphoric acid esters than dichlorvos are also indicated, but with different sensitivities.
||After performing the required 10 pump strokes the reagent ampoule must be broken and the liquid transferred to the enzyme layer by gently tapping the side of the tube. The substrate layer must not become wet After waiting one (1) minute the liquid must be carefully drawn up to the marking line using the pump. Wait another minute before drawing the liquid onto the indication layer using the pump.