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CHEMets Formaldehyde Visual Method
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CHEMets Formaldehyde Visual Method
The CHEMets Method To perform a test, immerse the CHEMet ampoule into the sample and snap off the tip (Step 1)- the correct volume of sample is automatically drawn in, filling the ampoule; a small inert gas bubble remains in the ampoule. To facilitate mixing the sample and reagent, tilt the ampoule back and forth so the bubble travels from end to end (Step 2). In 2 minutes or less, quantify the result by comparing the filled ampoule to the appropriate color standard(s) (Step 3). For higher concentrations, the flat comparator is used. For lower concentrations, the round comparator is used. The ampoule is compared with the standards until a color match is found. Kits include 30 ampoules, comparator(s), accessory solution(s)(when necessary), a sample cup, and instructions. Refill packs of 30 ampoules and accessory solutions are available separately. Comparators have a 2-year shelflife. Material Safety Data Sheets are provided in test kits. CHEMets ampoules are designed for maximum simplicity and accuracy. Each glass ampoule is 7 mm in diameter, 100 mm in length, with a tapered, pre-scored tip; reagents are vacuum-sealed inside.
Product Description
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 Shiffs'reagent or chromotropic acid procedures. A purplecolored 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: six months. We recommend stocking quantities that will be used within five months. Refrigeration will dramatically extend the shelf-life of these products.
Visual Kits
Range: 0-1 & 1-5 ppm
MDL: 0.05 ppm / Method: Purpald
Cat# CHEMets Kit K-4605
CHEMets Refill, 30 ampoules, Shelf-life 6 months R-46052
Activator Solution Pack, six 20 mL bottles A-42011, 3
Activator Solution Pack, six 10 mL bottles, Shelf-life 2 years A-42021
Low Range Comparator, Shelf-life 2 years: 0, 0.1, 0.2, 0.3, 0.4, 0.6, 0.8, 1.0 ppm C-4601
High Range Comparator, Shelf-life 2 years: 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0 ppm C-4605
Kit comes in a plastic case and contains everything needed to perform 30 tests (except distilled water): Refill, Low and High Range Comparators, Activator Solutions, 25 mL sample cup, instructions, and MSDS.