They may look shiny from a glance, but they're not as slippery as one might think. Perhaps if they had been recently washed after getting a lot of dirt, they might be wet, but for the most part, they aren't as dangerous as some would think. Regardless, epoxy-floors are very safe, and unless you are using specific footwear, you are not at risk. Even when you spill liquid, the waterproof characteristics of the epoxy coat will ensure that the liquid will follow the path of least resistance and flow away from the initial spot and spread. It is, however, important to not let the liquid evaporates on its own to avoid stains over time.