Survival of Microorganisms on Filtering Respiratory Protective Devices Used at Agricultural Facilities

Abstract

Bioaerosol is a threat at workplaces, therefore the selection and safe use of filtering facepiece respirators (FFRs) is important in preventive activities. The aim of the study was to assess the survival of microorganisms on materials used for FFRs construction. The parameters for microorganism growth under model conditions were described using the Gompertz equation, model verification was also carried out using FFRs at the farmers’ workplaces. We found that the factors determining a high survival of microorganisms were as follows: moisture corresponding to the conditions of use and storage of FFRs at workplaces, the presence of sweat and organic dust; inorganic dust and addition of biocide in nonwovens limited the growth of microorganisms, resulting in a shortening of the stationary growth phase and decreased cell numbers (5–6 log). Dust concentration at workplaces was higher than EU occupational exposure limit values and WHO recommendations for airborne particulate matter. Microbial contaminations of the air (103–104 CFU/m3), settled dust (104–106 CFU/g) and FFRs (105 CFU/4cm2) during the grain harvest were high, the main contamination being bacteria (actinomycetes, Pseudomonas fluorescens) and xerophilic fungi. A high correlation was found between the number of microorganisms and the weight of dust on FFRs (R2 = 0.93–0.96).

The efficiency of nuisance relief by filtering facepiece respirators used by workers exposed to agricultural odours

“…In this study, the microbiological contamination levels of FFRs were consistent with data from a combined heat and power station processing plant biomass [26]. Nevertheless, the microbial counts were lower than those reported by Jachowicz et al [18] in an agricultural setting, where a half-mask worn by a combine harvester operator harboured up to 10 5 CFU/4 cm 2 of both bacteria and fungi after just an hour of use. Such discrepancies suggest that FFR contamination can vary based on the specific workplace and its microclimatic conditions, such as humidity and air temperature.…”

“…Such discrepancies suggest that FFR contamination can vary based on the specific workplace and its microclimatic conditions, such as humidity and air temperature. Jachowicz et al also highlighted a strong correlation between environmental dust levels and microbial counts on FFRs [18]. In this study, the average air temperature in livestock rooms was around 13°C, and PM concentrations adhered to legal guidelines, aligning with the findings of low FFR microbial contamination in this setting.…”

“…Regarding another safety aspect of livestock breeding, exposure to microorganisms originating from animals and their dwelling environment, it is significant to select the adequate protection class of the protective equipment and determine the time of its safe use. Numerous studies confirmed that during a long-term use of respiratory protective equipment (RPE), microorganisms counts might increase and biofilm can be created in the filtering non-woven, which constitutes a potential hazard source for the equipment user [16][17][18]. The problem becomes critical when equipment is used multiple times or for extended periods, a common practice among self-employed individuals.…”

Aplikacja Time4Mask wspomagająca dobór sprzętu ochrony układu oddechowego przed bioaerozolem i monitorowanie czasu jego stosowania

“…podczas przerobu biomasy, w kompostowni, sortowni odpadów lub cementowni. Pozwoliło to na zebranie zestawu danych empirycznych i doświadczeń, które bezpośrednio odnoszą się do oceny czasu bezpiecznego stosowania filtrującego SOUO w środowisku pracy, gdzie występuje ryzyko inhalacji szkodliwych cząstek bioaerozolu [14][15][16][17][18][19][20].…”