Comment on: Penetration of Ultrafine Particles and Ion Clusters Through Wire Screens by Ichitsubo et al.

Arecent paper by the authors (Heim et al. 2005) examined the filtration efficiency of nanoparticles in the 2.5–20 nm size range, in an attempt to determine if thermal bounce occurs. The work included a critical review of previous work, including the work of Ichitsubo et al. (1996), which was the only paper found by the authors which appeared to detect actual “thermal rebound.” Further investigation of the results and methods used by Ichitsubo et al. (1996), have allowed us to conclude with a high degree of certainty, that the results shown can be attributed to the poor sizing performance of the DMA used rather than actual particle thermal bounce effects.