Due to toxicity issues, only one suitable Polyalphaolefin, PAO-4, a 4 centistokes (4 cSt) synthetic aliphatic hydrocarbon, may be used in Filter Leak Testing.
ATI’s position is that PAO-4 with a CAS # 68649‐12‐7 is acceptable by FDA definition.
Since the release of the aforementioned CGMP note, ATI has conducted testing of other 4 cSt PAO products, CAS# of 68037‐01‐4, and found that there is no measurable differences in the particle size distribution, standard deviation or leakage measurements obtained, using either polydisperse Laskin III-A and thermal condensation generators, or near mono-disperse controlled nebulizers.
Please note, other polyalphaolefin products may be available; however 4 cSt PAO (PAO-4) is the only suitable DOP/DEHP (dioctylphthalate/Diethylhexylphthalate) aerosol reagent.
Please Note: Varieties of PAO that have viscosity ratings other than 4 cSt might not generate aerosols having similar characteristics and MAY be potentially hazardous.