The sanitizers are totally safe, we use them in hospitals, schools and nursing homes. Envirocon and Oxine are chlorine based products manufactured specifically for ventilation system usage. They are EPA registered products and will kill mold, dust mites and many types of bacteria. They leave no lasting residue and break down to simple table salt. Envirocon is indicated for use in homes where people are present. Oxine usage recommends that the customer leave the home for 1 hour after it is applied. Click here for more information regarding the products we use.