What safety precautions should I follow when using the HPA250B Air Purifier?

The air purifier must always be used in its upright position and should never be used outdoors, near water, or where combustible gases are present. Do not use an extension cord or power strip, do not block air outlets or intakes, and always turn the unit OFF and unplug it when not in use or before servicing. Filters may be harmful if ingested, so keep the unit out of reach of children and pets, and avoid breathing dust when changing filters. (Page 2)