Nanosafer Sample Clauses

Nanosafer. Nanosafer10 was developed by the National Research Centre for the Working Environment (NRCWE) and the Danish Technological Institute (DTI) in Denmark, in collaboration with the Danish Industry, the Branch Organization for Industry Workers, and the Ministry for Science and Education (Kristensen et al., 2010). The tool provides a risk evaluation in the near and far-field for short (15 minutes) and long-term (8-hours) exposure for occupational exposures involving potential inhalation of MN as respirable dust, i.e. handling powders, releases from grinding which release dust with a known or assumed fraction of NM (NOAA) in the airborne fraction and in case of spills. In contrast to ART, the Nanosafer considers the near field to be the space around the source, rather than the worker (which means that a worker can be either in the near-field or the far-field). The tool estimates whether the material is nano-relevant from the input parameters (i.e. particles ≤ 200 nm and/or products with a specific surface area (SA) ≥ 30 m2 g-1). The emission rate for a process is determined within the tool, based on either dustiness data (Eo) adjusted for the activity energy (hi) and applied mass-flow (dM/dt) or a constant release rate (Ei,o). A first- order quantitative two-box aerosol dispersion model, as with most of the higher tier models, is then used to determine the near-field (NF) and far-field (FF) concentrations. In addition to the dust transport between the two compartments, the aerosol decay rates are in principle considered as function of the ventilation rates, efficiencies of exposure control, ingression of particles from other sources, coagulation, and aerosol surface deposition by diffusion and sedimentation (Xxxxxxxxx et al., 2011). In the simplified Nanosafer model, only the calibrated aerosol transport and decay rates from the NF to the (FF (NFNF-FF) and from the FF to the NF (Xxxxxxx, 1999) are considered in the assessment as well as the residual concentration in the NF and FF. NF = ⎡ QNF ⋅ CFF ⎤ ⋅ [Q ⋅ Δt + e(−QNF ⋅Δt ) −1] FF → NF ⎢Δt ⋅ (Q )2 ⎥ NF ⎣ NF ⎦ NF = ⎡QNF ⋅ CNF ⋅ (Ei ⋅ Δt )⎤ ⋅ [Q ⋅ Δt + e(−QNF ⋅Δt ) −1] NF →FF ⎢ ⎣ Δt ⋅ (QNF ) ⎥ NF ⎦ ⎡ (C + C )⎤ NFresidual = ⎢0.5 ⋅ ⎣ NF ,t−1 (QNF NF ,t ⋅ dt) ⎥ ⋅ [1 − e(−QNF ⋅dt ) ] ⎦ ⎡ (C + C )⎤ FFresidual = ⎢0.5 ⋅ ⎣ FF ,t −1 (QFF FF ,t ⋅ dt ) ⎥ ⋅ [1 − e(−QFF ⋅dt ) ] ⎦ The output from Nanosafer is an integrated risk assessment for short-term (15 min) and 8-hour NF and FF exposure. The risk scaling is based on compila...