Particulate Matter in the Air of the Underground Chamber Complex of the Wieliczka Salt Mine Health Resort.

This study evaluates the mass concentration and chemical composition of particulate matter (PM), collected in the chamber complex of the underground health resort located in the Wieliczka Salt Mine in southern Poland. Physical and chemical properties of PM were examined from the standpoint of their possible connection with therapeutic effects of the subterranean air in the mine. We found that in three underground spots we measured the average concentration of PM did not exceed 30 µg/m3. Chemical composition of PM was dominated by sodium chloride, making up 88 % of its mass, on average. It was shown that the underground ambient concentration of PM and its chemical composition depended mostly on the nature of the rock material present in the ventilation tunnel of the health resort, filtering the incoming air. The presence and effect of external sources of PM, including patients' activity, also had an impact on the underground PM concentration.

Fungal aero-decontamination efficacy of mobile air-treatment systems.

Immunosuppressed patients are at high risk of acquiring airborne fungal infections, mainly caused by Aspergillus species. Although HEPA filters are recommended to prevent environmental exposure, mobile air-treatment units can be an alternative. However, many different models of mobile units are available but there are few data on their fungal aero-decontamination efficacy and usefulness in the prevention of Aspergillus infections. Thus, we developed a challenge test, based on the aerosolization of 10(6) Aspergillus niger conidia, in order to compare the particle and fungal decontamination efficacy of the following four mobile air-treatment systems; Plasmair T2006, Mobil'Air 1200 (MA1200), Mobil'Air 600 (MA600) combined with Compact AirPur Mobile C250 (C250), and the prototype unit Compact AirPur Mobile 1800 (C1800). The use of all these air-treatment systems was able to significantly decrease the concentration of particles or fungal viable conidia. ISO7 was the maximum particle class reached within 20 min with the Plasmair T2006 and MA1200, 1 h by the combined MA600/C250, and 1 h and 30 min with the C1800. After 2 h, fungal counts were significantly lower with Plasmair T2006, MA1200 and the combined MA600/C250 (2.2 ± 1.9 to 5.0 ± 3.7 CFU/m(3)) than achieved with the C1800 (23.8 ± 12.8 CFU/m(3); P ≤ 6.0E-3). All the air-treatment systems were able to decrease aerial particle and fungal counts, but their efficacy was variable, depending on the units' air-treatment modalities and rates of air volume that was processed. This comparative study could be helpful in making an informed choice of mobile units, and in improving the prevention of air-transmitted fungal infections in non-protected areas.

A 'whole building' path to climate control.

With September having seen the end of the registration period for the introductory phase of the Carbon Reduction Commitment (CRC) Energy Efficiency Scheme, healthcare sector participants should already be monitoring their energy usage, and preparing their carbon reduction strategies. John Durbin, engineering department manager at air conditioning equipment specialist Daikin U.K., argues that, to minimise an organisation's legal liabilities and trade successfully in carbon allowances, a holistic view should be taken of climate control systems across health estates--"and that means incorporating the latest heat recovery techniques".

A pilot study of bioaerosol reduction using an air cleaning system during dental procedures.

BACKGROUND: Bioaerosols are defined as airborne particles of liquid or volatile compounds that contain living organisms or have been released from living organisms. The creation of bioaerosols is a recognized consequence of certain types of dental treatment and represents a potential mechanism for the spread of infection. OBJECTIVES: The aims of the present study were to assess the bioaerosols generated by certain dental procedures and to evaluate the efficiency of a commercially available Air Cleaning System (ACS) designed to reduce bioaerosol levels. METHODS: Bioaerosol sampling was undertaken in the absence of clinical activity (baseline) and also during treatment procedures (cavity preparation using an air rotor, history and oral examination, ultrasonic scaling and tooth extraction under local anaesthesia). For each treatment, bioaerosols were measured for two patient episodes (with and without ACS operation) and between five and nine bioaerosol samples were collected. For baseline measurements, 15 bioaerosol samples were obtained. For bioaerosol sampling, environmental air was drawn on to blood agar plates using a bioaerosol sampling pump placed in a standard position 20 cm from the dental chair. Plates were incubated aerobically at 37°C for 48 hours and resulting growth quantified as colony forming units (cfu/m³). Distinct colony types were identified using standard methods. Results were analysed statistically using SPSS 12 and Wilcoxon signed rank tests. RESULTS: The ACS resulted in a significant reduction (p = 0.001) in the mean bioaerosols (cfu/m³) of all three clinics compared with baseline measurements. The mean level of bioaerosols recorded during the procedures, with or without the ACS activated respectively, was 23.9 cfu/m³ and 105.1 cfu/m³ (p = 0.02) for cavity preparation, 23.9 cfu/m³ and 62.2 cfu/m³ (p = 0.04) for history and oral examination; 41.9 cfu/m³ and 70.9 cfu/m³ (p = 0.01) for ultrasonic scaling and 9.1 cfu/m³ and 66.1 cfu/m³ (p = 0.01) for extraction. The predominant microorganisms isolated were Staphylococcus species and Micrococcus species. CONCLUSION: These findings indicate potentially hazardous bioaerosols created during dental procedures can be significantly reduced using an air cleaning system.

[Importance of air purifiers in the prevention of respiratory allergy]. / Intérêt des purificateurs d'air dans la prévention de l'allergie respiratoire.

Prevention of respiratory allergy and thus diminution of its prevalence consists of the application not only of preventative measures on the allergens themselves, but also on atmospheric pollutants such as NO, CO and diesel particles. These modify the allergens and increase synthesis of allergen-specific IgE. Use of air purifiers, on condition that they have HEPA or ULPA filters may contribute to reduction of allergenicity linked to pollutants and are one of the not-negligible means of protection from respiratory allergy and asthma in particular.

Potential applications of differential permeability membranes in the control of gas composition in closed circuit atmospheres.

Long hyperbaric exposures of humans, at pressures in excess of 2.5 atmospheres, require that the oxygen concentration of the breathing gas be maintained at levels less than atmospheric air, in order to prevent pulmonary oxygen toxicity. Carbon dioxide produced by humans must be removed from the breathing gas of closed environments. Differential permeability gas separation devices can be used to reduce the concentrations of carbon dioxide and oxygen in recirculating nitrogen/oxygen atmospheres. The application of these devices can eliminate the requirement for nitrogen to dilute oxygen, and reduce, or eliminate, the requirement for carbon dioxide absorbents. The use of differential permeability gas separation devices for the production of nitrogen/oxygen breathing gas mixtures for divers, using air as a source gas, can produce mixtures with unacceptably high levels of carbon dioxide.

Closed circuit, multiperson, lung-powered rebreathers for hyperbaric oxygen treatment.

During the conceptual design of a "fly away" Submarine Rescue System (SRS) for the US Navy, a closed circuit breathing system for hyperbaric oxygen treatment was chosen to reduce the weight and volume of the necessary oxygen stores used in decompression treatments. A multiperson, human-powered breathing system was modeled and analyzed for potential development. The potential development of a prototype will allow empirical testing of performance parameters such as breathing, resistance, oxygen concentration, and hyperbaric gas analysis. As a spinoff of the multiperson concept, the modification of commercial off-the-shelf closed circuit air rebreathers are now being considered as an alternative for development. Each concept has benefits and limitations in providing a solution to the procurement of a key component to the SRS.

[Allergen-free wards in the treatment of pollinoses and bronchial asthma]. / Bezallergennye palaty v lechenii pollinozov i bronkhial'noi astmy.

Two allergen-free wards (AFW) fitted out with Academician I. V. Petryanov's filters have been in operation in the Department of General Allergy of the Institute of Immunology, USSR Ministry of Health, since 1981. A high AFW efficacy was shown during treatment without drugs of pollinosis patients with grave manifestations in the pollination season and patients with atopic bronchial asthma outside the season of plant pollination. Since 1981 treatment in AFW has been provided to 232 patients, of them in 104 with a good effect in the season of plant pollination.