Sensitivity and reliability are two important issues for membrane integrity testing.
Sensitivity of a membrane direct integrity-testing method is likely to govern the removal
credit granted to a membrane system. The recent data from a microbial challenge test on
production plant scale validated the sensitivity of integrity-testing method the first time
and demonstrated high sensitivity of the pressure-hold test for a membrane system.
Reliability, defined as the ability of an integrity-testing method, has not been a regulatory
focus. However, it is a crucial issue when establishing upper control limit (UCL) for
indirect integrity monitoring. The reliability of a membrane integrity-testing method can
be evaluated via probabilities of false negative and false positive signals generated by a
method and monotonic response to increasing severity of membrane integrity-breach.
Because of randomness of a measurement, an UCL has to be established based on some
statistical characteristics of a sample population. Recent data indicated that many of the
indirect integrity-testing methods are not only low in sensitivity, but also unreliable,
which makes indirect-integrity monitoring rather difficult to implement. Includes 9 references, tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 480 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 11 |
| Published : | 11/15/2004 |
