Can you add an additive to a penetrant?

Another faithful reader and customer asked if there was an additive that could be used to facilitate the electrostatic spraying of penetrant.
While the question was innocently made, the person either forget or did not understand that the penetrant in use was a QPL approved material under AMS-2644. As such, its composition is frozen and may not be changed without renaming the material and then having it requalified.

This is a time consuming and laborious process. Adding something to the approved penetrant can have unexpected results. The sensitivity level might change, the washability characteristics may also change, and the formulation might change to be either toxic or corrosive. One cannot tell beforehand, which is why the formulations are essentially frozen to be identical with what was approved under the AMS 2644 qualification tests.