Pall recommends the use of water to lubricate the O-rings of a filter in order to ease installation into the housing.

Pall does not recommend the use of alcohol (or an alcohol/water mixture) as it could come into contact with the filter membrane, causing a hydrophilic spot that will allow water passage, resulting in a false failure test result, especially in a water intrusion test.

Additionally, if any alcohol gets trapped between the two O-rings grooves, there will be a localized area where the alcohol will expand when the filter is sterilized (autoclave or steam-in-place).  This can potentially damage the filter adapter, or impact the filter to housing seal.

For more information, please see Pall Publication, USD 3033 Application Note: Best Practices for Successful Filter Integrity Testing Using the Water Intrusion Test (WIT) Method