On January 22, 2007, ISO published a report entitled Workplace Atmospheres — Ultrafine, Nanoparticle and Nano-Structured Aerosols — Inhalation Exposure Characterization and Assessment, which includes information on the potential health effects of nanoaerosols, sources of occupational nanoaerosols, exposure assessment strategies, particle ensemble characterization methods, size-resolved characterization, online chemical analysis, single particle analysis, and electron microscopy sample collection and preparation. The report states that its aim is “to provide generally accepted definitions and terms, as well as guidelines on measuring occupational nanoaerosol exposure against a range of metrics.” ISO intends the report to address an immediate need and establish an essential step for developing future exposure assessment standards for nanoaerosols.