Yes. Dioctyl phthalate aerosols also called Di (2-ethylhexyl) phthalate, di-sec octyl phthalate, DOP, or DEHP, have long been used to test the integrity of HEPA filters but concern about the potential health effects to people working with DOP test aerosols has led to a search for a safer equivalent replacement. The product of choice from US Army testing with assistance from various private companies was a Henkel Corporation (Emery Group) product called Emery 3004 PAO. This product is a polyalphaolefin (POA) in the 4 centistoke (4 cSt) viscosity grade, used primarily as a lubricant base stock for oils, lubricants, and electrical/hydraulic fluids. Emery 3004 (POA) can replace DOP in HEPA integrity testing.