Green Cleaning, Sanitizing, and Disinfecting: a Curriculum for Early Care and Education.
https://www.epa.gov/sites/default/files/2013-08/documents/ece_curriculum_final.pdf

According to the following cleaning guidelines, prepared by the University of California and available on the EPA website, steam cleaners are “devices that clean, sanitize or disinfect surfaces” (page 19).

“Disinfecting kills 99.999% of germs on hard, non-porous surfaces or objects. [...] Some devices can be used to disinfect; for example machines that apply steam to surfaces. These devices are very effective, work quickly, and use no chemicals. Some are mops and others look like a canister vacuum with attachments for use on different surfaces. They can also disinfect surfaces that chemical disinfectants cannot, such as upholstery and carpets.” (page 20).

“Steam cleaners can be used to sanitize, deodorize, and remove grease, dirt, and product residues thoroughly and quickly without chemicals. They can be used on many surfaces, including bathroom fixtures, floors and countertops, carpeting, and upholstery. Dry vapor steam cleaners use super-heated low moisture steam – no chemicals – for disinfecting, sanitizing, and cleaning surfaces. They are very effective and approved for food contact as well as other surfaces including carpets and upholstery. They are one of the most effective ways to remove bacteria that have formed a biofilm.” (page 38)

“Dry vapor steam cleaners have been shown to be very effective for disinfecting and is approved for food contact surfaces as well as other surfaces.” (page 41)