Nanotechnology is the understanding, manipulation, and control of matter at dimensions of roughly 1 to 100 nanometers, which is near-atomic scale, to produce new materials, devices, and structures. One nanometer is one-billionth of a meter. Putting this size into perspective, a single human hair is about 80,000 nanometers in width and a red blood cell is about 7,000 nanometers in diameter.

Health Effects Nanotechnology at the National Institute for Occupational Safety and Health (NIOSH). NIOSH is the leading federal agency providing guidance and conducting research on the occupational safety and health implications and applications of nanotechnology. Nanotechnology and the Environment.

Engineered nanoscale materials or nanomaterials are materials that have been purposefully manufactured, synthesized, or manipulated to have a size with at least one dimension in the range of approximately 1 to 100 nanometers and that exhibit unique properties determined by their size.