The move then was made to the permanent lab, I had very good facilities. We had then – what we don't have now – we had what were called, are called, sterile rooms. They were very small rooms outfitted with work surfaces and ultraviolet lamps. These small rooms lined both sides of my rather large lab, and it was in these rooms that you did your sterile work with cell culture, of course the... one of the main problems with culturing human and animal cells in bottles and flasks is to keep out microorganisms, because if they fall in the soup in which the cells are growing, they will grow better than the cells and foul up any experiment you are doing by contaminating the cells. So the purpose of these small rooms was to achieve that goal of maximum sterility.

We did not have what we now have today, which are filters of such small diameter holes that they can filter out bacteria, they're called 'Hepa Filters', they did not exist. We relied substantially on ultra violet lamps, which of course kill whatever is on a surface but not what's not under a thin surface. And those lights were turned on every night in these small sterile rooms, turned off the next morning, and people worked in these... I think I had five or six of these small workrooms.