Exposure standards have not been established for engineered nanoparticles in the United States or internationally [Safe Nanotechnology 2008.] Until more definitive findings are made regarding the potential health risks of handling nanomaterials, researchers planning to work with nanomaterials must implement a combination of engineering controls, work practices, and personal protective equipment to minimize potential exposures to themselves and others. For a quick guide to the exposure risks and prudent control measures to be used for common laboratory operations involving nanomaterials, refer to the table. It is important to consider if the nanoparticles are in an agglomerated or aggregated form, functionalized, suspended in liquid, or bound, as these conditions may affect the exposure potential.
- Engineering Controls:
- Use glove bags, glove boxes, fume hoods, or other containment or exhausted enclosures when there is a potential for aerosolization, such as: handling powders; creating nanoparticles in gas phase; pouring or mixing liquid media which involves a high degree of agitation. (DO NOT use horizontal laminar flow hoods (clean benches), as these devices direct the air flow towards the worker.) Consult with EH&S if engineering controls are not feasible.
- Use fume hoods or other local exhaust devices to exhaust tube furnaces and or chemical reaction vessels.
- Perform any maintenance activities, such as repair to equipment used to create nanomaterials or cleaning/replacement of dust collection systems, in fume hoods or under appropriate local exhaust.
Personal Protective Equipment:
- Selection of Nanomaterials:
- Whenever possible, handle nanomaterials in solutions or attached to substrates to minimize airborne release.
- Consult the Material Safety Data Sheet (MSDS), if available, or other appropriate references prior to using a chemical or nanomaterial with which you are unfamiliar. Note: Information contained in some MSDSs may not be fully accurate and/or may be more relevant to the properties of the bulk material rather than the nano-size particles.
- Safety Equipment:
- Know the location and proper use of emergency equipment, such as safety showers, fire extinguishers, and fire alarms.
- Do not consume or store food and beverages, or apply cosmetics where chemicals or nanomaterials are used or stored since this practice increases the likelihood of exposure by ingestion.
- Do not use mouth suction for pipetting or siphoning.
- Wash hands frequently to minimize potential chemical or nanoparticle exposure through ingestion and dermal contact.
- Remove gloves when leaving the laboratory, so as not to contaminate doorknobs, or when handling common use objects such as phones, multiuser computers, etc.
- Labeling and Signage:
- Store in a well-sealed container, preferable one that can be opened with minimal agitation of the contents.
- Label all chemical containers with the identity of the contents (avoid abbreviations/ acronyms); include term "nano" in descriptor (e.g., "nano-zinc oxide particles" rather than just "zinc oxide." Hazard warning and chemical concentration information should also be included, if known.
- Use cautious judgment when leaving operations unattended: i) Post signs to communicate appropriate warnings and precautions, ii) Anticipate potential equipment and facility failures, and iii) Provide appropriate containment for accidental release of hazardous chemicals.
- Wet wipe and or HEPA-vacuum work surfaces regularly.
- Use sealed, double-contained container when transporting nanomaterials inside or outside of the building.
- Buddy System:
- Communicate with others in the building when working alone in the laboratory; let them know when you arrive and leave. Avoid working alone in the laboratory when performing high-risk operations.
- Wear gloves, lab coats, safety goggles, long pants, closed-toe shoes, and face shields, as appropriate dependent on the nature of the materials and procedure.
- If work cannot be conducted inside a fume hood or other ventilated enclosure, consult with EH&S's Occupational Health and Safety Program (723-0448) regarding the need for respiratory protection or other alternative controls.
Standard Operating Procedures:
- Ensure that researchers have both general safety training and lab-specific training relevant to the nanomaterials and associated hazardous chemicals used in the process/experiment. See SU's Laboratory Chemical Safety Toolkit (SU Toolkit) for guidance on training (http://chemtoolkit.stanford.edu/ChemSafetyTraining)
- Lab-specific training can include a review of this safety fact sheet, the relevant Material Safety Data Sheets (if available), and the lab's Standard Operating Procedure for the experiment.
- Prepare a Standard Operating Procedure (SOP) for operations involving nanomaterials. A general use Standard Operating Procedure for working with nanomaterials is available here. The SOP should be tailored to be specific to the proposed experimental procedure.
- Consider the hazards of the precursor materials in evaluating the process.
- Special consideration should be given to the high reactivity of some nanopowders with regard to potential fire and explosion. [Pritchard 2004].
Consult with your Principal Investigator prior to procuring or working with nanomaterials. See SU's Toolkit for information regarding consultation and prior approvals (http://chemtoolkit.stanford.edu/PriorApprovals). For additional assistance, contact EH&S's Occupational Health & Safety Program at 723-0448.
Back to General Principles and Practices for Working Safely with Engineered Nanomaterials