Pneumologie | 2021
[Investigation of the Filter Performance in a Sample of Standardised Particle-filtering Half Masks].
Abstract
BACKGROUND\n\u2002Thanks to a simplified special approval process that was valid until October 1st, 2020, a large number of particle-filtering half masks have come onto the German market. When caring for SARS-CoV-2 infected patients, the RKI recommends wearing particle-filtering half masks with a filter performance of at least 94\u200a%, which corresponds to FFP class 2 according to EN 149:2001+A1:2009. We have examined 15 particle-filtering half masks with different specifications for their filter performance METHOD: \u2002The masks were clamped in a jig in an airtight test box. Radioactive particles with a size of 0.6\u200a±\u200a0.4\u200aµm were nebulized into the box and sucked into a filter through the port of the jig and an unfiltered reference port using an artificial lung. The activity deposited on the filter was measured by means of a gamma camera. The filter performance was calculated from this.\n\n\nRESULTS\n\u2002Five of the 15 masks tested had a filter performance of less than 94\u200a% and therefore do not meet the FFP2 standard. The filter performance of these masks was 71.8\u200a±\u200a2.3\u200a%, 73.2\u200a±\u200a2.3\u200a%, 78.2\u200a±\u200a6.7\u200a%, 92.2\u200a±\u200a0.5\u200a% and 85.9\u200a±\u200a1.6\u200a%.\n\n\nCONCLUSION\n\u2002One third of the examined masks did not meet the recommended FFP2 standard, which is recommended for the care of SARS-CoV-2 infected patients. A comprehensive review of already approved products by the supervisory authorities is advisable.