Filters that pass the overall efficiency test may still have minute pinhole leaks. AstroCel filters can be factory scanned to assure there are no pinhole leaks. Scanning detects these leaks which are repaired before the filter is released for shipment. AAF uses a proprietary static scan test with a challengeaerosol of non-toxic, polyfunctional alcohol that leaves no residue on the media. For pharmaceutical and those applications requiring DOP or PAO, AAF offers scanning with these materials using a light scattering photometer.