Formaldehyde Test Kits
Visual Kits
| Range | MDL | Method | Kit Catalog No. | Refill Catalog No. |
|---|---|---|---|---|
| 0-1 & 1-10 ppm | 0.1 ppm | Purpald | K-4605 | R-4605 |
| 0-30 & 30-300 ppm | 5 ppm | Purpald | K-4605D | R-4605D |
| 0-60 & 60-600 ppm | 10 ppm | Purpald | K-4605A | R-4605A |
| 0-120 & 120-1200 ppm | 20 ppm | Purpald | K-4605B | R-4605B |
| 0-1200 & 1200-12,000 ppm | 200 ppm | Purpald | K-4605C | R-4605C |
Method
Formaldehyde, a toxic substance, is used in the following applications: metal plating baths, textile treatments, biological specimen preservatives, and disinfectants of medical equipment. Commercial formaldehyde gas is readily soluble in water.
The Purpald Method
Reference: Purpald® developed by Aldrich Chemical Co.
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.