Figure 1

Sidestream nebulizer aerosol size distribution. Aerosol size is on the X-axis is plotted against the normative and cumulative underside aerosol distributions. The blue boxes profile the normative size distribution of nebulized perflubron, the near symmetry suggests a log-normal distribution of aerosol particles. The red squares plot the same data but as a cumulative size distribution of particle size against cumulative undersize %. The cumulative size distribution is used to interpolate the MMAD as the particle size at 50% of the cumulative mass – in this case the MMAD is 1.1 um. The Geometric Standard Deviation (GSD) of the MMAD is calculated using the intercepts at 15.8% and 84.1% (approximated by grey lines in Figure) using the formula GSD = sq rt (size 84.1um / size 15.8 um).