The drive for greater efficiency continues to stimulate debate as to whether full-resolution, multiple-stage cascade impaction still needs to be applied to the extent that it is currently.
The Reduced Next Generation Impactor (rNGI) is an abbreviated method for utilising the NGI in both AIM-QC and AIM-HRT applications.
In the same way as with the Fast Screening Andersen (FSA), depending on the flow rate to be used, a stage of the NGI can be selected having a cut-off diameter close to the product MMAD (in the case of an rNGI-QC application) or close to 5 microns (in the case of a rNGI-HRT application).
A paper filter held in place with a special rNGI Filter Holder Assembly is now placed in the top of the stage immediately after that of the one selected.
On operating the rNGI, particles smaller than the cut-off diameter of the stage preceding the filter will be captured on the filter, whilst particles larger than that stage will impact as normal in the collection cups of those stages upstream.
For comprehensive product details, specifications and part numbers, please request a copy of our brochure “Quality Solutions for Inhaler Testing”.
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