By far, the most toxic characteristic of chlorine dioxide gas is through inhalation. Inhalation of even moderate levels for a period of time can be fatal. For this reason, all application processes are done by DeepReach personnel under strict guidelines. The space to be treated is cordoned off, placarded and continuously monitored by DeepReach personnel assuring the safety of all involved.
The second most exposure of concern is the eyes, as chlorine dioxide is very soluble in water and will readily dissolve in the moisture found there. ClO2 is a very pungent gas, one which would be hard to tolerate at or above 5 PPM. The odor is just noticeable at PEL, 0.1 PPM and is quite noticeable at Stel, 0.3 PPM . The required protective equipment for working with levels of chlorine dioxide at or below 5 PPM is for the use of a full faced respirator with 3M cartridge 6006, long sleeved shirt and long pants. The compound is an IARC category III (Not likely to be a carcinogen) and is currently being evaluated for category IV, Not a carcinogen. Anyone accidently exposed to the gas would immediately recognize the burning in eyes and would seek to evacuate the area, which in turn becomes a benefit of the properties of the gas being noticable before being seriously injured. Similiar to feeling the heat of a fire before being burned by it.
The use of a fumigant is always associated with some risk. The safety procedures put into place in the safety and handling section of the label, as well as the operations sections were stringent enough to allow USEPA to determined the process, during their risk assessment to be a reasonably manageable risk. With multiple containments, gas detectors both inside and outside the containment area, a written fumigation plan in place and an existing evacuation procedure in place, no undue risk was determined. With multiple containments in place there has never been any type of containment breach or worker exposure in the 6 years of DeepReach Oxidation operation.