Hold the ampoule in a horizontal position while the capillary tip contacts the sample (Step 1). After the capillary fills, immerse it in a diluent (usually deionized water); snap the tip off the ampoule (Step 2). The sample and diluent are drawn into the ampoule where they mix with the reagent (Step 3). The resulting color change can then be compared with the flat or round comparator to quantify results (Step 4).

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. Most comparators have a 2-year shelf-life. Material Safety Data Sheets are provided in test kits.

VACUettes ampoules are designed for highly concentrated samples. They employ a patented auto-dilution feature that eliminates the need for a time-consuming and error-prone preliminary dilution. As a result, the entire test takes only 2 to 3 minutes, with a rate of accuracy comparable to a volumetric procedure. The basic design of these 7 mm ampoules is the same as CHEMets ampoules, however, a capillary tip is attached to the tip of each ampoule.