Effectiveness of half masks for respiratory health protection in coal mining

An improved procedure is presented for testing the level of respiratory health protection and comfort of half masks currently used in coal mining and similar industries. This will allow companies to make the best choice of such equipment for their workers. Half masks used by one Slovenian (PV) and two Polish (JSW and PPG) coal mining companies were tested in terms of filtering efficiency, especially for PM2.5, perceived effectiveness, comfort and ease of use. Filtering efficiency was determined by analysing filters from masks used in underground operations for the levels and sizes of trapped coal dust particles and by carrying out experiments employing a specially developed laboratory test stand. The latter incorporated a replica human head and a climatic chamber to simulate the humidity of exhaled air during mining activities. To determine the comfort and utility of the half masks, selected miners were asked to fill in questionnaires. The main results of these studies were that, in the interest of miners' health, and for those working in other high dust environments, the quality of the half-mask should be assessed on the basis of workplace and stand tests. These are complementary and both should be included to ensure the correct assessment of the half masks. For the masks supplied by the mentioned mining companies, their filtering efficiency for PM2.5, as determined using the test stand, was excellent at over 99%.

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Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2021).