Can’t ventilate it? Scrub it! Not every site is easily ventilated to the outdoors, often because of security issues, and many commercial buildings offer no practical access to the outdoors. When ventilation isn’t an option, it is important to provide adequate air exchanges of at least 6 air changes per hour (ACH). Carbon Filtration—the Key Ingredient An activated carbon filter-equipped air scrubber like the HEPA 700 not only adsorbs smoke odors, it also is useful for many other types including solvent or petrochemical odors, sewer gas and related odors, food and cooking odors, and many other strong, objectionable odors such as those from dead animals. Activated carbon is also useful for ozone odors.
Make sure to place the carbon filter closest to the inlet, then the pleated paper prefilter - that allows the prefilter to block larger particles before they reach the HEPA primary filter.
Pay special attention to your prefilters—change them often and you’ll extend the life of your HEPA primary filter. Prefilters should be changed whenever the accumulation of dust and debris is visible. Replace carbon filters when a simple “sniff-test” tells you they’re no longer removing odors. The HEPA 700 unit's Command Hub displays information about the health of the HEPA filter and shows a "Service" alert when the HEPA filter needs replacing.