Steam is the new buzzword when it comes to cleaning your home. The sales of products that use steam to clean floors, countertops, tiles and even sinks have more than doubled to $335 million since 2008. And 24 manufacturers now make steam mops, canister steam cleaners and hand-held steam cleaners.
Steam mops, which cost $50–$160, are made for cleaning hard floors. Steam canisters, or canisters, which cost $90–$1,600, have mop attachments that clean hard floors, but they also have other attachments that allow you to clean countertops, upholstery, tile grout, ovens or grills. However, canister models that cost more than $500 typically are beyond what most consumers need, because these models produce steam for at least 2 hours, which is what you’d get from a commercial steam cleaner. Hand-held steam cleaners, which cost $40–$150, can’t mop floors, but they will handle many of the other jobs that canisters can tackle. It’s just that they do so on a smaller scale.
What makes a steam cleaner appealing is that it uses only hot water to eliminate germs and bacteria as effectively as chemical-based cleaning products do. But steam cleaners vary in the way that they create steam, and they vary in the maximum steam temperature that they generate. Steam temperatures that manufacturers list for each model and the way that each manufacturer measures steam temperature is a particular problem for consumers. Independent experts whom we interviewed say steam that’s 212 degrees Fahrenheit (or perhaps even lower than that temperature) is hot enough to tackle most cleaning tasks at home.
HEATED DEBATE. Most manufacturers measure a steam cleaner’s steam temperature from the spray nozzle, which provides the most accurate indication of how hot the steam will be when it hits the surface that has to be cleaned. But other manufacturers measure steam temperature from the boiler tank, where the water would be hottest. Of course, steam temperature decreases as soon as it leaves the boiler tank—by as much as 30 degrees in just 5 inches, depending on the density of the steam, according to steam-cleaner manufacturer Haan.
All of this can make for a maddening shopping experience for consumers. For instance, we found steam mops that listed temperatures of as high as 248 degrees that were measured from the nozzle tip and a staggering 347 degrees that were measured in the boiler tank. But the models that have the highest steam temperatures won’t deliver better cleaning results, according to the independent experts whom we interviewed. Steam that’s produced in normal conditions—at room temperature—is 212 degrees, yet experts say that as long as steam is 140 degrees, it will kill enough bacteria to sanitize a surface.
Nonetheless, 10 manufacturers claim that a few of their models heat steam at a temperature that’s higher than 212 degrees. Those manufacturers tell us that the increased steam temperature isn’t about killing more germs but about delivering more cleaning power, because steam that’s hotter than 212 degrees does a better job of penetrating uneven surfaces, such as tile grout, and soft surfaces, such as mattresses, when it’s compared with steam temperatures of 212 degrees or lower.
It’s true that steam that’s hotter than 212 degrees will kill more bacteria if it’s used in a contained environment, such as the autoclave devices that some hospitals use to sterilize medical tools. But in the real-world environment of your home, steam that’s 212 degrees is hot enough to kill germs and bacteria for most cleaning jobs, says Jay Garland, who is in charge of microbiological research at Environmental Protection Agency.
CLEANING POWER. The only problem with having low-temperature steam—say, 150 degrees—is that you must apply the steam for more time, says Andrew Milkowski, who is an adjunct professor at University of Wisconsin and a bacteria-research specialist. That doesn’t mean that models that have steam temperatures that are lower than 212 degrees are necessarily a bad choice; it’s just that the cleaning task will take longer.