On Wed, 12 Sep 2007 02:48:17 +0000, Larry wrote:

And, it takes a lab test to see if it's safe
boaters don't have, placing WAY TOO MUCH FAITH in the integrity of that
membrane, I think.

There is a simple test for chlorides: just add a drop of silver
nitrate solution to a sample. Any hint of cloudiness would indicate a
leak. This is how the steamship boys tested their boiler water for
leaks in the condenser. Your conductivity test should also find a hole
in the membrane. I also think there are many who would
not bother to check: you may be right about 'too much faith'.
Lots of people simply trust the stuff to be good, when they fill up
with whatever comes out of the hose at the marina. It wouldn't be that
hard to add a conductivity meter to the RO equipment at the factory.
How often do the membranes fail, anyway?

Casady