Yes, you should use an oil-free steamer to clean your mattress. There are a lot of benefits that come with using an oil-free steamer. 1. It helps prevent mold and mildew from growing on the mattress which is known to cause allergic reactions in some people. 2. It also helps eliminate dust mites and their droppings by killing them with steam. 3. The heat generated by the steamer kills bacteria as well as kills any viruses or other harmful organisms that may be present on the mattress. 4. It is also much healthier to your skin as it helps dry all the oils out of the pores. 5. It is also very easy to clean (and sanitize) the oil-free steamer after you are done.