Hi Kathleen: Unless something has changed lately, pretty certain that viruses (definitely including HIV, less sure of Hepatitis) transmitted via body fluids die rather quickly when exposed to air. Chance of transmission is slim, but I wouldn't encourage using friend's or relative's kit--would at least mention potential risks. There are so many bacteria, viruses and fungi, an LC would need an advanced degree in bacteriology to reassure that no risk is involved. (Not to mention risk associated with chips, scratches, etc. due to wear and tear.) I didn't mean to imply that you reuse kits as demos clients can try out. Only meant that I am aware of some LCs who do, so I wanted to mention liability issues. Sorry if that caused you any discomfort--certainly wasn't intended. Karen