Detection of viable antibiotic‐resistant/sensitive Acinetobacter baumannii in indoor air by propidium monoazide quantitative polymerase chain reaction

Acinetobacter baumannii represents a significant cause of nosocomial infections. Therefore, we combined real‐time quantitative polymerase chain reaction (PCR) with the propidium monoazide (PMA‐qPCR) to assess the feasibility of detecting viable, airborne A. baumannii. The biological collection efficiencies of three samplers for collecting airborne A. baumannii were evaluated by PMA‐qPCR in a chamber study. After sampling, the effects of storage in collection fluid on A. baumannii were evaluated. The results showed that the culturable ratio of A. baumannii measured using the culture method was significantly correlated with the viable ratio measured using PMA‐qPCR, but was not significantly correlated with the qPCR results. It was indicated that the AGI‐30 impinger and the BioSampler were much more effective than the Nuclepore filter sampler for collecting airborne A. baumannii. The storage temperature was critical for aerosol samples, as the loss of viable A. baumannii was minimized when the PMA‐bound DNA was stored at ?20°C or if the collected cells were stored at 4°C and subsequently processed by PMA‐qPCR within 1 month. The PMA‐qPCR method was also to distinguish between colistin‐sensitive and colistin‐resistant A. baumannii, and no colistin‐sensitive A. baumannii was detected by PMA‐qPCR upon treatment of the BioSampler collection medium with 2 μg/ml colistin for 5 min.     

Assessing exposure to secondhand smoke in restaurants and bars 2 years after the smoking regulations in Beijing,China

Field observation of patron smoking behaviors and multiple sampling approaches were conducted in 79 restaurants and bars in Beijing, 2010, 2 years after implementing the governmental smoking regulations. Smoking was observed in 30 visits to 22 of the 37 nominal non‐smoking venues during peak patronage times and six visits to four of the 14 nominal non‐smoking sections. The median area secondhand smoke (SHS) concentrations during peak patronage time were 27, 15, 43, and 40 μg/m³ in nominal non‐smoking venues, non‐smoking sections, smoking sections, and smoking venues, respectively, as indicated by the difference between indoor and outdoor PM_2.5 levels; and 1.4, 0.6, 1.7, and 2.7 μg/m³, respectively, as indicated by airborne nicotine. In the 27 venues with sampling of different approaches and over different time periods, the median nicotine concentration was 1.8 μg/m³ by one‐hour peak patronage‐time sampling, 1.1 μg/m³ by 1‐day active area sampling, 2.5 μg/m³ by 1‐day personal sampling, and 2.3 μg/m³ by week‐long passive sampling. No significant differences in nicotine levels were observed among venues/sections with different nominal smoking policies by all sampling approaches except during peak patronage time. This study showed that the 2008 Beijing governmental smoking restriction has been poorly implemented, and SHS exposures in Beijing restaurants and bars remain high.     

Unexpected increase in indoor pollutants after the introduction of a smoke‐free policy in a correctional center

Correctional centers (prisons) are one of the few non‐residential indoor environments where smoking is still permitted. However, few studies have investigated indoor air quality (IAQ) in these locations. We quantified the level of inmate and staff exposure to secondhand smoke, including particle number (PN) count, and we assessed the impact of the smoking ban on IAQ. We performed measurements of indoor and outdoor PM_2.5 and PN concentrations, personal PN exposure levels, volatile organic compounds (VOCs), and nicotine both before and after a complete indoor smoking ban in an Australian maximum security prison. Results show that the indoor 24‐h average PM_2.5 concentrations ranged from 6 (±1) μg/m³ to 17 (±3) μg/m³ pre‐ban. The post‐ban levels ranged from 7 (±2) μg/m³ to 71 (±43) μg/m³. While PM_2.5 concentrations decreased in one unit post‐ban, they increased in the other two units. Similar post‐ban increases were also observed in levels of PN and VOCs. We describe an unexpected increase of indoor pollutants following a total indoor smoking ban in a prison that was reflected across multiple pollutants that are markers of smoking. We hypothesise that clandestine post‐ban smoking among inmates may have been the predominant cause.     

Exercise‐induced effects on a gym atmosphere

We report results of analysis of a month‐long measurement of indoor air and environment quality parameters in one gym during sporting activities such as football, basketball, volleyball, badminton, boxing, and fitness. We have determined an average single person's contribution to the increase of temperature, humidity, and dust concentration in the gym air volume of 12500 m³: during 90‐min exercise performed at an average heart rate of 143 ± 10 bpm, a single person evaporated 0.94 kg of water into the air by sweating, contributed 0.03 K to the air temperature rise and added 1.5 μg/m³ and 5 ng/m³ to the indoor concentration of inhalable particles (PM₁₀) and Ca concentration, respectively. As the breathing at the observed exercise intensity was about three times faster with respect to the resting condition and as the exercise‐induced PM₁₀ concentration was about two times larger than outdoors, a sportsman in the gym would receive about a sixfold higher dose of PM₁₀ inside than he/she would have received at rest outside.     

Characterization and pro‐inflammatory responses of spore and hyphae samples from various mold species

Mold particles from Aspergillus fumigatus, Penicillium chrysogenum, Aspergillus versicolor, and Stachybotrys chartarum have been linked to respiratory‐related diseases. We characterized X‐ray‐inactivated spores and hyphae fragments from these species by number of particles, morphology, and mycotoxin, β‐glucan and protease content/activity. The pro‐inflammatory properties of mold particles were examined in human bronchial epithelial cells (BEAS‐2B) and THP‐1 monocytes and phorbol 12‐myristate 13‐acetate (PMA)‐differentiated THP‐1. Spores from P. chrysogenum and S. chartarum contained some hyphae fragments, whereas the other preparations contained either spores or hyphae. Each mold species produced mainly one gelatin‐degrading protease that was either of the metallo‐ or serine type, while one remains unclassified. Mycotoxin levels were generally low. Detectable levels of β‐glucans were found mainly in hyphae particle preparations. PMA‐differentiated THP‐1 macrophages were by far the most sensitive model with effects in the order of 10 ng/cm². Hyphae preparations of A. fumigatus and P. chrysogenum were more potent than respective spore preparations, whereas the opposite seems to be true for A. versicolor and S. chartarum. Hyphae fragments of A. fumigatus, P. chrysogenum, and A. versicolor enhanced the release of metalloprotease (proMMP‐9) most markedly. In conclusion, species, growth stage, and characteristics are all important factors for pro‐inflammatory potential.     

Air quality,mortality, and economic benefits of a smoke – free workplace law for non‐smoking Ontario bar workers

We estimated the impact of a smoke‐free workplace bylaw on non‐smoking bar workers' health in Ontario, Canada. We measured bar workers' urine cotinine before (n = 99) and after (n = 91) a 2004 smoke‐free workplace bylaw. Using pharmacokinetic and epidemiological models, we estimated workers' fine‐particle (PM_2.5) air pollution exposure and mortality risks from workplace secondhand smoke (SHS). workers' pre‐law geometric mean cotinine was 10.3 ng/ml; post‐law dose declined 70% to 3.10 ng/ml and reported work hours of exposure by 90%. Pre‐law, 97% of workers' doses exceeded the 90th percentile for Canadians of working age. Pre‐law‐estimated 8‐h average workplace PM_2.5 exposure from SHS was 419 μg/m³ or ‘Very Poor’ air quality, while outdoor PM_2.5 levels averaged 7 μg/m³, ‘Very Good’ air quality by Canadian Air Quality Standards. We estimated that the bar workers' annual mortality rate from workplace SHS exposure was 102 deaths per 100 000 persons. This was 2.4 times the occupational disease fatality rate for all Ontario workers. We estimated that half to two‐thirds of the 10 620 Ontario bar workers were non‐smokers. Accordingly, Ontario's smoke‐free law saved an estimated 5–7 non‐smoking bar workers' lives annually, valued at CA $50 million to $68 million (US $49 million to $66 million).     

Controlled experiments measuring personal exposure to PM2.5 in close proximity to cigarette smoking

Few measurements of exposure to secondhand smoke (SHS) in close proximity to a smoker are available. Recent health studies have demonstrated an association between acute (<2 h) exposures to high concentrations of SHS and increased risk of cardiovascular and respiratory disease. We performed 15 experiments inside naturally ventilated homes and 16 in outdoor locations, each with 2–4 non‐smokers sitting near a cigarette smoker. The smoker's and non‐smokers' real‐time exposures to PM_2.5 from SHS were measured by using TSI SidePak monitors to sample their breathing zones. In 87% of the residential indoor experiments, the smoker received the highest average exposure to SHS, with PM_2.5 concentrations ranging from 50–630 μg/m³. During the active smoking period, individual non‐smokers sitting within approximately 1 m of a smoker had average SHS exposures ranging from negligible up to >160 μg/m³ of PM_2.5. The average incremental exposure of the non‐smokers was higher indoors (42 μg/m³, n = 35) than outdoors (29 μg/m³, n = 47), but the overall indoor and outdoor frequency distributions were similar. The 10‐s PM_2.5 averages during the smoking periods showed great variability, with multiple high concentrations of short duration (microplumes) both indoors and outdoors.     

Ventilation strategies and indoor particulate matter in a classroom

Particle mass and number concentrations were measured in a mechanically ventilated classroom as part of a study of ventilation strategies for energy conservation. The ventilation system was operated either continuously, intermittently, or shut down during nights while it was on during workdays. It appears that the nighttime ventilation scheme is not important for indoor particle concentrations the following day if fans are operated to give five air exchanges in advance of the workday. The highest concentrations of PM₁₀ were found during and after workdays and were due to human activity in the classroom. The average workday PM₁₀ concentration was 14 μg/m³, well below the WHO guideline values. The number concentration of particles with diameter <0.750 μm was typically between 0.5 × 10³ and 3.5 × 10³ particle/cm³. These concentrations were largely independent of the occupants. Transient formation of small particles was observed when ventilation was shut down. Then remaining ozone reacted with terpenes emitted by indoor sources and gave up to 8 × 10³ particle/cm³ before formation stopped due to lack of ozone. The intermittent ventilation regime was found least favorable for the indoor air quality in the classroom.     

Fine and ultrafine particle exposures on 73 trips by car to 65 non‐smoking restaurants in the San Francisco Bay Area

A number of studies indicate cooking is a major source of exposure to particulate matter, but few studies have measured indoor air pollution in restaurants, where cooking predominates. We made 73 visits by car to 65 different non‐smoking restaurants in 10 Northern California towns while carrying portable continuous monitors that unobtrusively measured ultrafine (down to 10 nm) and fine (PM_2.5) particles to characterize indoor restaurant exposures, comparing them with exposures in the car. The mean ultrafine number concentrations in the restaurants on dinner visits averaging 1.4 h was 71 600 particles/cm³, or 4.3 times the mean concentration on car trips, and 12.3 times the mean background concentration in the residence. Restaurants that cooked dinner in the same room as the patrons had higher ultrafine concentrations than restaurants with separate kitchens. Restaurant PM_2.5 mass concentrations averaged 36.3 μg/m³, ranging from 1.5 to 454 μg/m³, but were relatively low on most visits: 43% of the indoor means were below 10 μg/m³ and 66% were below 20 μg/m³, with 5.5% above 100 μg/m³. Exposure to fine and ultrafine particles when visiting a restaurant exceeded the exposure a person received while traveling by car to and from the restaurant.     

Isothiazolone emissions from building products

Adding biocides to dispersion products is a well‐known practice to control microbial deterioration. Isothiazolones are among the most commonly used preservatives, in particular a mixture of 2‐methyl‐2H‐isothiazol‐3‐one (MIT) and 5‐chloro‐2‐methyl‐2H‐isothiazol‐3‐one (CIT). In recent years, for health reasons, due to its strong sensitizing effect, CIT has been replaced by 1,2‐benzisothiazol‐3‐one (BIT). Furthermore, numerous products are now available for interiors containing the fungicidal active substance 2‐octyl‐2H‐isothiazol‐3‐one (OIT). So far nearly nothing is known of the emission behavior of BIT and OIT. An analytical method was developed for these two isothiazolones and interior products containing BIT respectively OIT have been investigated in an emission chamber and in test rooms. The chamber tests revealed maximum concentrations of 6.7 μg OIT/m³, 1.9 μg BIT/m³, and 187 μg MIT/m³. Concentrations obtained in the test rooms were at levels up to 1.4 μg OIT/m³ and 29 μg MIT/m³. A noticeable finding was the very slight subsidence of OIT and BIT levels over several weeks. While MIT outgassed quickly, OIT in particular showed low concentrations, but prolonged evaporation.     

Enrichment of bacteria possessing catechol dioxygenase genes in the rhizosphere of Spirodela polyrrhiza: A mechanism of accelerated biodegradation of phenol

The bacterial community structure in bulk water and in rhizosphere fractions of giant duckweed, Spirodela polyrrhiza, was quantitatively and qualitatively investigated by PCR-based methods using 6 environmental water samples to elucidate the mechanisms underlying selective accumulation of aromatic compound-degrading bacteria in the rhizosphere of S. polyrrhiza. S. polyrrhiza selectively accumulated a diverse range of aromatic compound-degrading bacteria in its rhizosphere, regardless of the origin of water samples, despite no exposure to phenol. The relative abundances of the catechol 1,2-dioxygenase (C12O) gene (C12O DNA) and catechol 2,3-dioxygenase (C23O) gene (C23O DNA) were calculated as the ratios of the copy numbers of these genes to the copy number of 16S rDNA and are referred to as the rhizosphere effect (RE) value. The RE values for C12O DNA and C23O DNA were 1.0 × 10¹–9.3 × 10³ and 1.7 × 10²–1.5 × 10⁴ times as high, respectively, in rhizosphere fractions as in bulk water fractions, and these higher values were associated with a notably higher sequence diversity of C12O DNA and C23O DNA. The RE values during phenol degradation were 3.6 × 10⁰–4.3 × 10² and 2.2 × 10⁰–1.7 × 10², respectively, indicating the ability of S. polyrrhiza to selectively accumulate aromatic compound-degrading bacteria in its rhizosphere during phenol degradation. The bacterial communities in the rhizosphere fractions differed from those in the bulk water fractions, and those in the bulk water fractions were notably affected by the rhizosphere bacterial communities. S. polyrrhiza released more than 100 types of phenolic compound into its rhizosphere as root exudates at the considerably high specific release rate of 1520 mg TOC and 214 mg phenolic compounds/d/g root (wet weight). This ability of S. polyrrhiza might result in the selective recruitment and accumulation of a diverse range of bacteria harboring genes encoding C12O and C23O, and the subsequent accelerated degradation of phenol in the rhizosphere.     

Classroom ventilation and indoor air quality—results from the FRESH intervention study

Inadequate ventilation of classrooms may lead to increased concentrations of pollutants generated indoors in schools. The FRESH study, on the effects of increased classroom ventilation on indoor air quality, was performed in 18 naturally ventilated classrooms of 17 primary schools in the Netherlands during the heating seasons of 2010–2012. In 12 classrooms, ventilation was increased to targeted CO₂ concentrations of 800 or 1200 ppm, using a temporary CO₂ controlled mechanical ventilation system. Six classrooms were included as controls. In each classroom, data on endotoxin, β(1,3)‐glucans, and particles with diameters of <10 μm (PM₁₀) and <2.5 μm (PM_2.5) and nitrogen dioxide (NO₂) were collected during three consecutive weeks. Associations between the intervention and these measured indoor air pollution levels were assessed using mixed models, with random classroom effects. The intervention lowered endotoxin and β(1,3)‐glucan levels and PM₁₀ concentrations significantly. PM₁₀ for instance was reduced by 25 μg/m³ (95% confidence interval 13–38 μg/m³) from 54 μg/m³ at maximum ventilation rate. No significant differences were found between the two ventilation settings. Concentrations of PM_2.5 and NO₂ were not affected by the intervention. Our results provide evidence that increasing classroom ventilation is effective in decreasing the concentrations of some indoor‐generated pollutants.     

Building and environmental factors that influence bacterial and fungal loading on air conditioning cooling coils

We investigated bacterial and fungal concentrations on cooling coils of commercial AC units and quantified associations between microbial loads and AC unit or building operational parameters. A field campaign was conducted to sample 25 AC units in the humid, subtropical climate of Southern CT, USA and 15 AC units in the hot‐summer Mediterranean climate of Sacramento, CA, USA. Median concentrations (with interquartile range) of bacteria and fungi on the cooling coils were 1.2 × 10⁷ (5.1 × 10⁶‐3.9 × 10⁷) cells/m² and 7.6 × 10⁵ (5.6 × 10⁴‐4.4 × 10⁶) spore equivalents (SE)/m², respectively. Concentrations varied among units with median unit concentrations ranging three orders of magnitude for bacteria and seven orders of magnitude for fungi. Controlled comparisons and multivariable regressions indicate that dominant factors associated with AC coil loading include the nominal efficiency of upstream filters (P = .008 for bacteria and P < .001 for fungi) and coil moisture, which was reflected in fungal loading differences between top and bottom halves of the AC coils in Southern CT (P = .05) and the dew points of the two climates considered (P = .04). Environmental and building characteristics explained 42% (P < .001) of bacterial concentration variability and 66% (P < .001) of fungal concentration variability among samples.     

Exposure to household air pollution from biomass cookstoves and blood pressure among women in rural Honduras: A cross‐sectional study

Growing evidence links household air pollution exposure from biomass cookstoves with elevated blood pressure. We assessed cross‐sectional associations of 24‐hour mean concentrations of personal and kitchen fine particulate matter (PM_2.5), black carbon (BC), and stove type with blood pressure, adjusting for confounders, among 147 women using traditional or cleaner‐burning Justa stoves in Honduras. We investigated effect modification by age and body mass index. Traditional stove users had mean (standard deviation) personal and kitchen 24‐hour PM_2.5 concentrations of 126 μg/m³ (77) and 360 μg/m³ (374), while Justa stove users’ exposures were 66 μg/m³ (38) and 137 μg/m³ (194), respectively. BC concentrations were similarly lower among Justa stove users. Adjusted mean systolic blood pressure was 2.5 mm Hg higher (95% CI, 0.7‐4.3) per unit increase in natural log‐transformed kitchen PM_2.5 concentration; results were stronger among women of 40 years or older (5.2 mm Hg increase, 95% CI, 2.3‐8.1). Adjusted odds of borderline high and high blood pressure (categorized) were also elevated (odds ratio = 1.5, 95% CI, 1.0‐2.3). Some results included null values and are suggestive. Results suggest that reduced household air pollution, even when concentrations exceed air quality guidelines, may help lower cardiovascular disease risk, particularly among older subgroups.     

Coarse particulate matter and airborne endotoxin within wood stove homes

Emissions from indoor biomass burning are a major public health concern in developing areas of the world. Less is known about indoor air quality, particularly airborne endotoxin, in homes burning biomass fuel in residential wood stoves in higher income countries. A filter‐based sampler was used to evaluate wintertime indoor coarse particulate matter (PM_10‐2.5) and airborne endotoxin (EU/m³, EU/mg) concentrations in 50 homes using wood stoves as their primary source of heat in western Montana. We investigated number of residents, number of pets, dampness (humidity), and frequency of wood stove usage as potential predictors of indoor airborne endotoxin concentrations. Two 48‐h sampling events per home revealed a mean winter PM_10‐2.5 concentration (± s.d.) of 12.9 (± 8.6) μg/m³, while PM_2.5 concentrations averaged 32.3 (± 32.6) μg/m³. Endotoxin concentrations measured from PM_10‐2.5 filter samples were 9.2 (± 12.4) EU/m³ and 1010 (± 1524) EU/mg. PM_10‐2.5 and PM_2.5 were significantly correlated in wood stove homes (r = 0.36, P < 0.05). The presence of pets in the homes was associated with PM_10‐2.5 but not with endotoxin concentrations. Importantly, none of the other measured home characteristics was a strong predictor of airborne endotoxin, including frequency of residential wood stove usage.     

Determinants of house dust,endotoxin, and β‐(1→3)‐D‐glucan in homes of Danish children

Little is known about the geographic variation and determinants of bacterial endotoxin and β ‐(1,3)‐d ‐glucan in Danish house dust. In a population of 317 children, we: (i) described loads and concentrations of floor dust, endotoxin, and β‐(1→3)‐d ‐glucan and (ii) their correlations and (iii) assessed their determinants; (iv) Finally, we compared our findings with previous European studies. Bedroom floor dust was analyzed for endotoxin content by the kinetic limulus amoebocyte lysate assay and for β‐(1→3)‐d ‐glucan by the inhibition enzyme immunoassay. The parents answered questions regarding potential determinants. We found: geometric means (geometric standard deviations) 186 mg/m² (4.3) for dust; 5.46 × 10³EU/m² (8.0) and 31.1 × 10³EU/g (2.6) for endotoxin; and 142 μg/m² (14.3) and 0.71 × 10³ μg/g (7.3) for β‐(1→3)‐d ‐glucan. High correlations (r > 0.75) were found between floor dust and endotoxin and β‐(1→3)‐d ‐glucan loads, while endotoxin and β‐(1→3)‐d ‐glucan concentrations were moderately correlated (r = 0.36–0.41) with the dust load. Having a carpet was positively associated with dust load and with endotoxin and β‐(1→3)‐d ‐glucan concentrations. Pet keeping, dwelling type, and dwelling location were determinants of endotoxin concentrations. No other determinants were associated with β‐(1→3)‐d ‐glucan concentrations. Compared with other European studies, we found lower β‐(1→3)‐d ‐glucan loads and concentrations but higher endotoxin loads and concentrations suggesting a geographically determined different composition of Danish floor dust compared with other European regions.     

Methods for quantifying Staphylococcus aureus in indoor air

Staphylococcus aureus has been detected in indoor air and linked to human infection. Quantifying S. aureus by efficient sampling methods followed by appropriate sample storage treatments is essential to characterize the exposure risk of humans. This laboratory study evaluated the effects of sampler type (all‐glass impinger (AGI‐30), BioSampler, and Andersen one‐stage sampler (Andersen 1‐STG)), collection fluid (deionized water (DW), phosphate‐buffered saline (PBS), and Tween mixture (TM)), and sampling time (3–60 min) on cell recovery. Effects of storage settings on bacterial concentration were also assessed over 48 h. Results showed BioSampler performed better than Andersen 1‐STG and AGI‐30 (P < 0.05) and TM was superior to PBS and DW (P < 0.05). An increase in sampling time negatively affected the recoveries of cells in PBS of BioSampler and AGI‐30 (P < 0.05), whereas cell recoveries in TM were increased at sampling of 6–15 min compared with 3 min. Concentrations of cells collected in PBS were decreased with storage time at 4 and 23°C (P < 0.05), while cells stored in TM showed stable concentrations at 4°C (P > 0.05) and increased cell counts at 23°C (P < 0.05). Overall, sampling by BioSampler with TM followed by sample transportation and storage at 4°C is recommended.     

Determination of low-density Escherichia coli and Helicobacter pylori suspensions in water

Determination of low-density of bacteria, especially those of pathogenic strains in water, has proven difficult and challenging. Here, we developed and evaluated a lanthanum-based concentration method coupled with quantitative real-time PCR to concentrate and detect selected bacteria (Escherichia coli and Helicobacter pylori) in water. To improve qPCR efficiency, the flocs with enmeshed bacteria after chemical flocculation need to be dissolved before PCR detection. Ethylenediaminetetraacetic acid (EDTA) salt successfully dissolved the flocs from a lanthanum-based flocculation process, but not those from the traditional processes using chemicals such as FeCl₃ or Al₂(SO₄)₃. Lanthanum-based concentration coupled with real-time PCR successfully determined E. coli at a concentration of 15 cells/mL in raw and finished water and H. pylori at a concentration of about 1 cell/mL in the finished water prior to disinfection. The H. pylori detection sensitivity could be easily increased to 60 cells/L by reducing the final volume of the DNA samples from 3 mL to 60 μL. With the elimination of membrane-clogging problem that is often encountered in direct membrane filtration, the lanthanum-based chemical flocculation coupled with qPCR is a promising method for determination of low-density of microbial suspensions in water.     

Impact of culture media and sampling methods on Staphylococcus aureus aerosols

Staphylococcus aureus has been detected indoors and is associated with human infection. Reliable quantification of S. aureus using a sampling technique followed by culture assay helps in assessing the risks of human exposure. The efficiency of five culture media and eight sampling methods in recovering S. aureus aerosols were evaluated. Methods to extract cells from filters were also studied. Tryptic soy agar (TSA) presented greater bacterial recovery than mannitol salt agar (MSA), CHROMagar staph aureus, Chapman stone medium, and Baird–Park agarose (P < 0.05). Moreover, 93 ± 2%–95 ± 2% and 42 ± 1%–49 ± 2% of S. aureus were, respectively, recovered by a 15‐min heating of gelatin filters and 2‐min vortex of polycarbonate (PC) filters. Evaluation of two filtration (IOM with gelatin filter and cassette with PC filter), two impaction (Andersen 1‐STG loaded with TSA and MSA) and four impingement methods [AGI‐30 and BioSampler filled with Tween mixture (TM) and phosphate‐buffered saline (PBS)] revealed the BioSampler/TM performed best over 30 and 60 min of sampling (P < 0.05), while low recovery efficiencies were associated with the IOM/gelatin, cassette/PC, and AGI‐30/PBS combinations (P < 0.05). In addition to BioSampler/TM, collecting S. aureus onto TSA from the Andersen 1‐STG is also recommended, as it is the second best method at the 60‐min sampling (P < 0.05).