Why should anyone use a laminar flow system ?
   What actually a laminar air flow system ?
   How are the High-efficiency particulate air ( HEPA filters) tested ?
   what specifications or standards apply to testing the filters in place ?
   Is this in-place filter test the same one as the filter manufacturer uses ?
   What is the procedure for in-place test?
   What does percent of penetration mean ?
   Why was 0.01% established as a significant ?
   Why can't the leak test be run with ambient air within a room ?
   If plates to obtain bacterial counts are used, must the in-place test still be run ?
   Can leaks not be detected by agar plates ?
   How about impingement devices ? 
   Is DOP aerosol harmful to the filters ?
   What happens to the DOP once it is in the system ?
   When DOP is used to test a system, does the room have to be wiped down ?
   Has DOP test been accepted by the pharmaceutical industry ?
   with reference to Fed. Std. 209b, What is the relationship of the various classes of clean rooms( 100, 10 000, and 100 000 ) to the 0.01% figure ?
   Can a particle counter not be used to determine the class of the room ?
   But isn't a particle count important data ?
   But, why can't leak test be carried out with a particle counters ?
   What are the advantages of the DOP in-place test over attempting a leak test with a particle counter ?
   How often should the DOP in-place test to be run ?
   What qualifications are necessary for in-place test personnel ?
   when should the HEPA filters be replaced ?
   Do all filter material makers and filter manufacturers use the same mehtods for testing their products ?