Hands-on toilet testing took place over more than 20 hours in our Lab, as well several months in our homes, where we were able to evaluate the toilets in real-world conditions. Rigorous lab tests were carried out by our engineers, who put each toilet through a battery of tests to find models that best combined performance and efficiency. This included tough clog tests involving colored powder, wads of toilet paper, sponges and even golf balls (though not all at once!). Our top toilets were able to handle more than 12 golf balls in a single flush (some upwards of 20!). We also used sensitive sound equipment to measure noise, knowing there may well be a sleeping baby in the next room. Home-based consumer testing focused on usability, with consumer testers assessing factors like comfort, cleanability and intuitiveness of any high-tech features.