For laboratory operations, “the order of preference (most preferred to least preferred) for handling nanomaterials is:

1. Solid materials with imbedded nanostructures
2. Solid nanomaterials with nanostructures fixed to the material’s surface
3. Nanoparticles suspended in liquids
4. Dry, dispersible (engineered) nanoparticles, nanoparticle agglomerates, or nanoparticles aggregates

Avoid handling nanomaterials in the open air in a ‘free particle’ state. Whenever possible, handle and store dispersible nanomaterials, whether suspended in liquids or in a dray particle form in closed (tightly sealed) containers.”¹

1. U.S. Department of Energy, Nanoscale Science Research Centers, “Approach to Nanomaterial ES&H,” 5-6 (Rev. 3a May 12, 2008).