The K-4605 CHEMets Visual Kit is visual indicator kit for measuring formaldehyde in water levels from 0-1 and 1-10 ppm. This device uses the Purpald Method for testing. Purpald® is subject to fewer interferences than Schiff's reagent or chromotropic acid procedures. A purple-colored complex is formed when Purpald in alkaline solution reacts with formaldehyde. Results are expressed as ppm (mg/L) CH2O.
Shelf-life of the Purpald Reagent: five months. We recommend stocking quantities that will be used within four months.
The refill kit R-4605 can be purchased for more tests.
- Low Range Comparator (0-2 ppm)
- High Range Comparator (0-10 ppm)
- Ampoules (30 tests)
- Activator Solutions
- 25 mL sample cup
- Instruction manual
How to use the K-4605:
- Fill the sample cup with 20 mL of sample water.
- Add 6 drops of A-4201 Activator Solution, and stir gently
- Add 4 drops of A-4202 Activator Solution, and stir gently
- Snap the end/tip of the ampoule in the water on the bottom/side of the 25 mL sample cup.
- Mix the contents of the ampule by tipping back and forth a few times.
- Dry the ampoule and wait 12 minutes for color development.
- Obtain the test result by matching to the corresponding color comparator.
- For the low range comparator: Place the ampoule, flat end first, into the comparator. Hold the comparator up towards a light source and view from the bottom. Rotate the comparator until the best color match is found.
Purpald Tech Sheet