b'HOMES MAY CONTAINOTHER HOMES MAY HAVE MATERIALS WITHUNVENTED SPACE HEATERSUNKNOWN LEVELS OR FIREPLACES THAT AREOF VOCS. NOT PROPERLY VENTED TOThese VOCs can off-gasTHE OUTSIDE.into the indoor air andThese fuel-burning sources cause eye and lungcan produce carbon monoxide, irritation and otherwhich is potentially deadly.health effects.'