Twll,
     Thanks so much. As luck would have it, Walgreens have a store about 1/4 
mile from where I live. Bob had also mentioned Wal-Mart. There is one of them 
about a mile away. I am getting the instrument that you can test it with so 
should be safe.  I don't think anyone has mentioned what the ppm reading should 
be to be considered safe.            Thanks again,       Bob Smith