Comparison of DOP Substitute Reagents for Use with TDA-5A and 5B Thermal Generators

Material	Block Temperature	Internal Pressure	Flow	Photometric Concentration	Results/Comments
DOP/DEHP	750-760°F	5 psig	10-11 lpm	60% with metering valve fully open	Aerosol stream stable, uniform and dry. Output remained stable and dry while varying the concentration across operating range.
DOS/DEHS	780-790°F	4.75 psig	6 lpm	75%	Aerosol stream dry and uniform. Clogging of the heater block occurred due to increased block temperature.
PAO-4 (Emery 3004)	760-775°F	5 psig	7 lpm	75%	Aerosol stream dry, uniform and stable throughout entire operating range. Increases in inert gas flow resulted in wet aerosol. Approved by FDA, DOE, US Army, Surgeon General as DOP replacement.
Ondina Oil	760-780°F	5 psig	7 lpm	75%	Aerosol stream is dry and stable. Wet aerosol occurred at < 670 °F.  Aerosol pulsation occurred at > 900 °F. Good replacement for DOP.
Corn Oil	750-760°F	5 psig	10 lpm	N/A	Aerosol stream wet. Increasing temperature and reducing inert gas flow resulted in no aerosol output at all. Not Acceptable.
Mineral Oil	750-760°F	5 psig	10 lpm	N/A	Aerosol stream semi-wet. Increasing the temperature while reducing inert gas flow dried aerosol but caused rapid clogging of heater block.