TESTING METHODOLOGY

    To evaluate water‑quality, I'll be using the HM Digital AP‑1 to measure Total Dissolved Solids (TDS) before and after filtration. TDS represents the total amount of dissolved matter in water, mainly ions like calcium, magnesium, and sodium, and is expressed in parts per million (ppm). Lower readings generally indicate fewer dissolved solids and cleaner output (water is left to settle briefly prior to immersing the AP‑1 probe). While this method provides a practical, real‑world snapshot of water purity, it cannot replace a full chemical analysis (something which obviously I can't do), which is required to identify specific contaminants or verify compliance with formal water‑quality standards.

    To measure operational behavior, I used three instruments. Noise levels are recorded with the ExTech HD600 decibel meter placed roughly one meter from the purifier, at the same height, while the unit was actively filtering and as for power consumption, it's tracked using the AVM FRITZ! Smart Energy 210, with separate measurements for cold‑water operation and hot‑water heating to capture realistic load conditions (when applicable). Finally, filtration speed was timed with a digital stopwatch, starting the moment filtration began and stopping when exactly one liter of purified water was collected. Each test will be repeated a total of 5 times to ensure consistency.