Uhmmm....

RichH wrote:

If a 0.000000000002 micrometer rated filter has enough surface area it
will operate with LESS differential pressure than a small surface area
filter with 3 METERS pore size.

Hardly! You need to study the issue of "bubble point" before making this
type of assertion. Basically, surface tension becomes the dominant
factor in backpressure when porosity is decreased to sub-micron levels.
In GENERAL, one can overcome delta-p issues due to lower average
porosity by increasing surface area, but certainly not allways.

Oh, and "small surface area" and "3 METERS" together do not make a
filter. It's a "HOLE". A BIG hole :-)

Keith Hughes