Refinement of the Nanoparticle Emission Assessment Technique into the Nanomaterial Exposure Assessment Technique (NEAT 2.0)

ABSTRACT

Engineered nanomaterial emission and exposure characterization studies have been completed at more than 60 different facilities by the National Institute for Occupational Safety and Health (NIOSH). These experiences have provided NIOSH the opportunity to refine an earlier published technique, the Nanoparticle Emission Assessment Technique (NEAT 1.0), into a more comprehensive technique for assessing worker and workplace exposures to engineered nanomaterials. This change is reflected in the new name Nanomaterial Exposure Assessment Technique (NEAT 2.0) which distinguishes it from NEAT 1.0. NEAT 2.0 places a stronger emphasis on time-integrated, filter-based sampling (i.e., elemental mass analysis and particle morphology) in the worker's breathing zone (full shift and task specific) and area samples to develop job exposure matrices. NEAT 2.0 includes a comprehensive assessment of emissions at processes and job tasks, using direct-reading instruments (i.e., particle counters) in data-logging mode to better understand peak emission periods. Evaluation of worker practices, ventilation efficacy, and other engineering exposure control systems and risk management strategies serve to allow for a comprehensive exposure assessment.

KEYWORDS:

• Emission
• nanomaterial
• NEAT
• occupational exposure assessment
• sampling

Acknowledgments

The authors extend special thanks to Mark Methner, Douglas Evans, Kevin H. Dunn, Alberto Garcia, and Kevin L. Dunn for their consultative expertise. In addition, the authors are grateful to Derk Brouwer of TNO and Thomas Peters of the University of Iowa for their review of this article.

Disclaimer

The findings and conclusions in this article are those of the authors and do not necessarily represent the official position of the National Institute for Occupational Safety and Health (NIOSH). The use of instrumentation and equipment by NIOSH during the refinement of NEAT 2.0 does not constitute endorsement. Equivalent instrumentation can be substituted.

Funding

The authors gratefully acknowledge the support of the NIOSH Nanotechnology Research Center cross-sector program (Paul A. Schulte and Charles L. Geraci, co-managers).