The Occupational Safety and Health Administration (OSHA) recently published a fact sheet entitled Working Safely with Nanomaterials. OSHA notes that workers who use nanotechnology in research or production processes may be exposed to nanomaterials through inhalation, skin contact, or ingestion. OSHA intends the fact sheet to provide “basic information to workers and employers on the most current understanding of potential hazards associated with this rapidly-developing technology and highlight measures to control exposure to nanomaterials in the workplace.” According to the fact sheet, information and training provided to workers should include:
- Identification of nanomaterials the employer uses and the processes in which they are used;
- Results from any exposure assessments conducted at the work site;
- Identification of engineering and administrative controls and personal protective equipment (PPE) to reduce exposure to nanomaterials;
- The use and limitations of PPE; and
- Emergency measures to take in the event of a nanomaterial spill or release.
OSHA states that there are few occupational exposure limits specific to nanomaterials. According to OSHA, because certain nanoparticles may be more hazardous than larger particles of the same substance, existing occupational exposure limits for a substance may not provide adequate protection from nanoparticles of the same substance. OSHA notes the following specific exposure limits:
- OSHA recommends that worker exposure to respirable carbon nanotubes and carbon nanofibers not exceed 7.0 micrograms per cubic meter (μg/m3) as an 8-hour time-weighted average, based on the National Institute for Occupational Safety and Health (NIOSH) proposed Recommended Exposure Limit (REL); and
- OSHA recommends that worker exposure to nanoscale particles of titanium dioxide (TiO2) not exceed NIOSH’s 0.3 milligrams per cubic meter (mg/m3) REL. By contrast, NIOSH’s REL for fine-sized TiO2 (particle size greater than 100 nm) is 2.4 mg/m3.
OSHA suggests that, because exposure limits for other nanomaterials do not exist yet, employers should minimize worker exposure by using the hazard control measures and best practices identified in the fact sheet and in the references noted.