[Evaluating efficiency of individual protective means for electromagnetic fields in radiofrequency range.]

In Russian Federation, absent regulation document for criteria and methods evaluating screening properties of protective means against radio frequency electromagnetic fields necessitates development of general principles and methods for indivual protective means testing. Findings are that indivual protective means testing are expedient with consideration of measurements in free space and evaluation of absorbed electromagnetic energy in tissue-equivalent phantoms. Screening coefficient should be assessed in several zones corresponding to location of human vital organs.

Occupational exposure to physical agents: the new Italian database for risk assessment and control.

This article presents the new Italian database of physical agents, which is available at http://www.portaleagentifisici.it. It supports in risk assessment employers who have to comply with Italy's Legislative Decree 81/2008 (transposing into law European Union Directives 2003/10/EC, 2002/44/EC, 2004/40/EC and 2006/25/EC). The database currently contains measurements and declared European Community (EC) values from over 2540 machines; in particular, the database hosts data on mechanical vibration from over 1430 hand-held power tools (e.g., pneumatic and electric hammers, chainsaws, grinders, drills, sanders and saws) and from over 1020 whole-body machines (e.g., buses, fork lifts and wheel tractors). The database is continuously updated as soon as new experimental and declared data are acquired.

[Occupational microclimate. Results and prospects of research].

The article covers results of studies conducted over last 15 years and aimed to elaboration of requirements to integral parameters of microclimate at workplace, its evaluation and regulation, prophylactic measures against body overcooling and overheating. The authors present methods to evaluate combined effects of physical factors (noise, vibration, microclimate) and to assess microclimate with consideration of factors determining body thermal load (energy expenditure, duration of stay at workplace, heat insulation of clothes and thermo-physical parameters of its materials). Mathematic models of forecasting cold and heat stress are presented, as well as requirements to heat insulation for individual protective means against cold and methods to calculate it. Regimens of work in heating and cooling conditions are specified. The authors set directions for further studies to define regulation requirements to microclimate on basis of studied patterns of body heat state formation, its evaluation criteria, epidemiologic studies results, specified prophylactic measures against overheating and overcooling with consideration of adaptation, sex, thermo-physical characteristics of individual protective means (special clothes, footwear, gauntlets, headwear).

The effect of disposable infection control barriers and physical damage on the power output of light curing units and light curing tips.

This study investigated the effects that disposable infection control barriers and physical damage through use had on the power output from dental light curing units (LCUs) and light curing tips (LCTs). Five disposable infection control barriers were tested on a number of LCUs and LCTs. Testing involved the repeated measurement of power output of LCUs and LCTs on a radiometer. Two of the barriers tested caused statistically significant reductions in the mean light output intensity when compared to the no barrier control groups. One barrier type reduced the power output by 30 to 40%. It was also noted that physical damage to the LCTs affected power output by between 20 and 30%, which was then further reduced by the disposable barrier. This study showed that three of the five disposable infection control barriers had little effect on the overall efficiency of the power output of the LCUs. It also showed that physical damage to LCUs and LCTs can affect power output significantly. Infection control measures should be carefully considered before use to avoid undue effects on power output delivered from the LCUs/LCTs to ensure that the degree of polymerisation within the resin-based composite and curing efficiency are not affected unduly.

Automatic exposure control in computed tomography--an evaluation of systems from different manufacturers.

BACKGROUND: Today, practically all computed tomography (CT) systems are delivered with automatic exposure control (AEC) systems operating with tube current modulation in three dimensions. Each of these systems has different specifications and operates somewhat differently. PURPOSE: To evaluate AEC systems from four different CT scanner manufacturers: General Electric (GE), Philips, Siemens, and Toshiba, considering their potential for reducing radiation exposure to the patient while maintaining adequate image quality. MATERIAL AND METHODS: The dynamics (adaptation along the longitudinal axis) of tube current modulation of each AEC system were investigated by scanning an anthropomorphic chest phantom using both 16- and 64-slice CT scanners from each manufacturer with the AEC systems activated and inactivated. The radiation dose was estimated using the parameters in the DICOM image information and image quality was evaluated based on image noise (standard deviation of CT numbers) calculated in 0.5 cm(2) circular regions of interest situated throughout the spine region of the chest phantom. RESULTS: We found that tube current modulation dynamics were similar among the different AEC systems, especially between GE and Toshiba systems and between Philips and Siemens systems. Furthermore, the magnitude of the reduction in the exposure dose was considerable, in the range of 35-60%. However, in general the image noise increased when the AEC systems were used, especially in regions where the tube current was greatly decreased, such as the lung region. However, the variation in image noise among images obtained along the scanning direction was lower when using the AEC systems compared with fixed mAs. CONCLUSION: The AEC systems available in modern CT scanners can contribute to a significant reduction in radiation exposure to the patient and the image noise becomes more uniform within any given scan.

Needlestick injury rates according to different types of safety-engineered devices: results of a French multicenter study.

OBJECTIVES: To evaluate the incidence of needlestick injuries (NSIs) among different models of safety-engineered devices (SEDs) (automatic, semiautomatic, and manually activated safety) in healthcare settings. DESIGN: This multicenter survey, conducted from January 2005 through December 2006, examined all prospectively documented SED-related NSIs reported by healthcare workers to their occupational medicine departments. Participating hospitals were asked retrospectively to report the types, brands, and number of SEDs purchased, in order to estimate SED-specific rates of NSI. Setting. Sixty-one hospitals in France. RESULTS: More than 22 million SEDs were purchased during the study period, and a total of 453 SED-related NSIs were documented. The mean overall frequency of NSIs was 2.05 injuries per 100,000 SEDs purchased. Device-specific NSI rates were compared using Poisson approximation. The 95% confidence interval was used to define statistical significance. Passive (fully automatic) devices were associated with the lowest NSI incidence rate. Among active devices, those with a semiautomatic safety feature were significantly more effective than those with a manually activated toppling shield, which in turn were significantly more effective than those with a manually activated sliding shield (P < .001, chi(2) test). The same gradient of SED efficacy was observed when the type of healthcare procedure was taken into account. CONCLUSIONS: Passive SEDs are most effective for NSI prevention. Further studies are needed to determine whether their higher cost may be offset by savings related to fewer NSIs and to a reduced need for user training.

Personal protective equipment in health care: can online infection control courses transfer knowledge and improve proper selection and use?

We used observational evaluation to assess the ability of an online learning course to effectively transfer knowledge on personal protective equipment (PPE) selection and removal. During orientations for new hospital staff, 117 participants applied either airborne, droplet, or contact precautions in mock scenarios. Postcourse, all 3 scenarios demonstrated improvement in PPE sequence scores (P = .001); moreover, hand hygiene also was more frequent during both donning and doffing of PPE (P < .001).

[Effectiveness of personal protective measures in prevention of nosocomial transmission of severe acute respiratory syndrome].

OBJECTIVE: To evaluate the effectiveness of personal protective measures of health care workers (HCWs) against severe acute respiratory syndrome (SARS). METHODS: A case-control study from ten hospitals in Guangdong, with 180 non-infected and 77 infected staff members that accessed the isolation unit every day, and participated in direct first aid for severe SARS patients. All participants were surveyed about how they were using personal protective equipment (PPE), protective drugs and hygiene habits when caring for patients with SARS. Statistical analysis was done with either chi(2) or Fisher's exact test for univariate analysis, whereas we used forward stepwise selection (Waldesian) for logistic regression. RESULTS: Univariate analysis showed that mask, gown, gloves, goggles, footwear, "hand-washing and disinfecting", gargle, "membrane protection", "taking shower and changing clothing after work", "avoid from eating and drinking in ward", oseltamivir phospha tall had protective effects (P < 0.05), but stepwise logistic regression showed significant differences for mask (OR = 0.78, 95% CI: 0.60 - 0.99), goggles (OR = 0.20, 95% CI: 0.10 - 0.41) and footwear (OR = 0.58, 95% CI: 0.39 - 0.86). Analysis for linear trend in proportions showed that dose response relationship existed in mask, gown, gloves, goggles, footwear, gargle, "membrane protection" and "taking shower and changing dree after work" (P < 0.01). The attack rate of HCWs who were rescuing severe SARS patients without any PPE was 61.5% (16/26). It seemed that the more the protective measures were used, the higher the protective effect was (P < 0.001), and could reach 100% if mask, gown, gloves, goggles, footwear, "hand-washing and disinfecting" were all used at the same time. CONCLUSIONS: Nosocomial infection of SARS can be prevented effectively by precautions against droplets and personal contact. HCWs must take strict protection according to the guidance of WHO or Chinese MOH and pay attention to personal hygiene.

Selection of needlestick prevention devices: a conceptual framework for approaching product evaluation.

Needlestick injuries have been associated with blood-borne disease transmission to health care workers. A demand for a safer work environment has contributed to a proliferation of "safety" products. The selection and evaluation of these devices differs from traditional product evaluation in that it considers not only effectiveness in patient care but also health care worker safety and cost-effectiveness in terms of prevention gained. In addition, multiple devices associated with injuries and choices between passive, active, and accessory safety options require that institutions establish priorities for focusing intervention efforts. Selection of products must involve the primary users. Unless new devices are found acceptable for patient care, health care workers are likely to reject them, despite any apparent safety advantages. Five project steps help define a systematic approach for this process: (1) creation of a multidisciplinary team, (2) defining prevention priorities on the basis of collection and analysis of an institution's injury data, (3) development of design and performance criteria for product selection according to needs for patient care and health care worker safety, (4) planning and implementing an evaluation of products in clinical settings, and (5) analyzing product performance and cost-effectiveness to choose the product. Several methodologic issues raise questions for future research in the area of product evaluation, including the selection of study populations, methods of product distribution and data collection, and influence of institutional culture. In addition, there is a need to develop product-specific design and performance criteria by which evaluation teams can measure various technologies under consideration. Standardization of the product evaluation process for needlestick prevention technology should lead to the collection of information that can be compared across institutions. Infection control professionals have an important opportunity to assume a leadership role in this process.

Estudo e avaliaçäo dos meios de biossegurança para o cirurgiäo-dentista e auxiliares contra doenças infecto-contagiosas no consultório odontológico / Evaluation of the methods for protection of dental team and prevention from infectious diseases

O presente trabalho visa alertar os cirurgiöes-dentistas para os perigos de transmissäo das doenças infecto-contagiosas no consultório odontológico e corrigir suas técnicas operatórias, visando o controle da infecçäo cruzada. Foram avaliados dispositivos de biossegurança, como máscaras faciais, máscaras retangulares e ovais, óculos e luvas existentes no comércio nacional. As luvas foram avaliadas com relaçäo à incidência de micro-perfuraçöes e localizaçäo dessas por horas de trabalho, e os outros dispositivos foram avaliados em relaçäo à eficiência, visibilidade e comodidade. Todos os dispositivos testados foram aprovados e indicados por serem eficientes