The original filter recommended by PNNL for the RASA is somewhat difficult to dissolve and has been discontinued by the manufacturer (3M) because the manufacturing process (substrate blown microfiber, or SBMF) has been superceded by a simpler process (scrim-free blown microfiber, or BMF). Several new potential filters have been evaluated by PNNL and by an independent commercial lab. A superior product has been identified which provides higher trapping efficiency, higher air flow, is easier to dissolve, and is thinner, accommodating more filters per RASA roll. This filter is recommended for all ground-based sampling, and with additional mechanical support, it could be useful for airborne sampling, as well.
Revised: August 28, 2006 |
Published: January 7, 2002
Citation
Thompson R.C., H.S. Miley, and R.J. Arthur. 2002.Filter Media Recommendation Review Richland, WA: Pacific Northwest National Laboratory.