Effectiveness of micronic aerosol generators and their aerosol characteristics

We assessed the effectiveness of various aerosol-generating systems. Taplin's settling method and Venticis generators had a lower efficiency (37.3 +/- 3.8% and 51.8 +/- 9.6%, respectively) than the Syntevent (88.8 +/- 6.9%, p less than 0.001), Cadema (89.8 +/- 9.9%, p less than 0.001) and Mefar (85.3 +/- 19.4%, p less than 0.001) generators. The Mass Median Aerodynamic Diameter of the particles produced by the Mefar nebulizer (2.05 +/- 0.27 micron) was larger than that of any other generators (p less than 0.001). The Syntevent (0.54 +/- 0.09 micron) generator produced smaller particles than the Mefar, Taplin (0.89 +/- 0.10 micron, p less than 0.01) and Venticis (0.79 +/- 0.06 micron, p less than 0.02) generators. Particles produced by the Cadema system (0.69 +/- 0.06 micron) were smaller than those generated by the Taplin system (p less than 0.05). We conclude: that the Syntevent, Mefar and Cadema aerosol generators are more efficient than the others, and that all the generators tested except the Mefar may be used for studies that depend on the peripheral deposition of small particles within the lungs.