Someone sent mail that I should have used the term inactivate for destroying or killing a virus. My apologies for not getting back to you. The term is the proper one. Some of the folks that I did a prepost discussion with, did not realise that inactivate also means to kill or destroy. I used the other terms for those who were not up to snuff on their biological terminology. My apologies to the list for using this forum for this, I accidently deleted his address. Byron