", solutions of ClO2 do not fog well and are prone to foaming, so gas generation is more effective and practical" " Gaseous ClO2 systems are available for fumigating laboratory rooms or suites of rooms up to 800 m3... Humidifiers and fans are used within the treated area to maintain relative humidity, typically in the 65% to 75% RH range, and to encourage uniform mixing of gas and moisture in the treated area." "All lights must be turned off in the room during decontamination as ClO2 broken down by UV light. With some commercial systems, to avoid corrosion damage, the decontamination device is placed outside the treated room and the gas piped in via a one-way valve."