Using a simulated faeces stain created by NASA, we assess cleanliness by checking how much of the stain is removed from a white tile. This is done by measuring the reflectance of the tile before applying the stain and again after cleaning.
How we test
We stain white tiles with the simulated faeces, then apply toilet cleaner to the tile and scrub it with a sponge attached to a mechanical arm. Reflectance is then measured and scored. Each product is tested three times, with the results averaged for a final score.
How we choose what we test
We aim to test brands and products you’re likely to see when you head to the shops, plus some you might not be aware of. Before we buy anything, we do our research – we visit stores (both online and physically), we talk to experts and consumers, and we ask manufacturers about their products. We want to capture new developments in the market and make sure the products we test will be available after we publish our results. We then compile a list of products and head out to purchase them, just as any consumer would.
Why is this free?
We’re dedicated to getting NZ consumers a fairer deal. We provide as much information as we can for free but we rely primarily on membership and donations to fund our work. You can help by becoming a Consumer member or making a donation. We’ll use your contribution to investigate consumer issues and work for positive change.