Qualitative Fitting Characteristics of Elastomeric Half Face-Piece Respirators Using Isoamyl Acetate Agent

To examine the fitting testing of elastomeric half face-piece respirators (EHRs), a total of 41 candidates were randomly assigned into seven EHRs equipped with organic vapor (OV) cartridges which were commonly used in the Iranian industrial workplaces. The qualitative fitting into the facial dimensions was assessed using the Allegro Isoamyl Acetate fit test kit. While the studied EHRs showed very low passing fit testing rates, the 3M, AoSafety (Medium), and AoSafety (Large) had the highest passing rates with 22.0%, 14.60%, and 9.76%, respectively. The AoSafety ‎(All sizes) delivered a higher passing fit test rate than the 3M brand (29.30 vs. 22.0%). The one size fits all respirators including the DUO and Climax showed lower proportions of passing fit tests compared with AoSafety three-size system brands (2.40% and 4.90% vs. 29.30%). Low fit test passing rates were determined among different respirators. The respirators with various sizes and styles had more opportunities for different wearers to pass the fit test than single size models. The initial and annual fit testing requirements shall be developed by local government. Also, the manufacturers are required to pay attention to respirator features and subject characteristics during the production to obtain satisfactory protection for the end-users

An assessment of dynamic pressure in buried tanks subjected to seismic loadings

The seismic performance of storage tanks is a matter of special importance, extending beyond the economic value of the tanks and contents. This has led to attention of many researchers due to the seismic behavior of tanks buried in the soil. Because of the interaction between soil and structure during an earthquake, dynamic analysis of such structures is very important that must be considered. In this paper, according to the interaction effect of soils and structures, under the time history record, seismic behavior of concrete cubic buried tanks has been analyzed using the finite element software ABAQUS. In this process circular and cubic tanks have been studied and the impact of changes in parameters such as earthquake and quantity of water in tanks on pressure on tank's wall has been studied

Investigating effective factors on risk perception, safety attitude and safety performance of construction workers of Shiraz city, 2012

Background and Aims: Construction sites are one of the most hazardous places in industries because of variety of activities, hazards and harmful agents. Therefore, workers employed in these sites are always exposed to risks of injuries. The aim of this study was to investigate the effective factors of risk perception, safety attitude and performance on construction workers.Materials and Methods: In this cross-sectional study, effective factors on risk perception, safety attitude and performance of 295 construction workers in Shiraz city were investigated. The study was conducted using a validated questionnaire which was completed through interview. Data were analyzed by using SPSS16. The level of significance was considered 0.05.Results: While the risk perception of 77.6 % of the study population was high, only 48.5 % had high safety attitude. However, 93.6% of construction workers had high safety performance. Among studied variables, association of risk perception with age, education and being witness of accident was significant. Moreover, the association of safety attitude with having insurance and safety performance with work experience, marital status and occurrence of accident for relatives was significant (p<0.05).Conclusion: The result of this study showed that by increasing risk perception of construction workers, their attitude and safety performance could be improved.Key words: Construction workers, Risk perception, Safety attitude, Construction sit

Psychometric Properties of the Persian Version of Consideration of Future Safety Consequence (CFSC) Scale

Background: Personality traits, due to having a relative stability, are important factors for predicting employees’ safety behavior. Consideration of Future Safety Consequence (CFSC) is a personality trait that was recently introduced to predict the safety behaviors. The purpose of this study was to translate and assess the psychometric properties of the Persian version of the CFSC scale. Methods: In the first stage of this cross-sectional study, the instrument was prepared by the forward-backward forward translation technique and evaluated by 487 employees of a gas refinery. The validity of the scale was evaluated through face, concurrent, validity, and construct validity. The safety performance questionnaire was used to examine the concurrent validity. The reliability of the questionnaire was evaluated using internal consistency (Cronbach’s alpha coefficient) and test-retest. Results: Content validity index was 0.885. The results of exploratory and confirmatory factor analysis indicated that the CFSC scale had a single factor. Also, Pearson correlation showed a positive correlation between the safety performance and the Persian version of CFSC (R=0.401). Test-retest reliability and internal consistency were calculated as 0.86 and 0.82, respectively. Conclusion: It is concluded that the psychometric properties of the Persian version of CFSC scale are desirable and can be used in future studie

Strategies for Controlling Violence Against Healthcare Workers: Application of Fuzzy Analytical Hierarchy Process and Fuzzy Additive Ratio Assessment

Objective: The present study aimed to identify and prioritize control measures of violence against Healthcare Workers (HWs) using the Fuzzy Analytical Hierarchy Process (FAHP) and Fuzzy Additive Ratio Assessment (F-ARAS). Background: Occupational violence is a pervasive problem in healthcare centers. Reducing violence against staff is one of the challenges for healthcare managers. Method: At the first stage, the most common criteria and control options for violence against HWs were identified and extracted using a review of previous studies. At the next stage, criteria for selection of control measures were prioritized using the FAHP. Finally, control measures of workplace violence were prioritized using the F-ARAS method. Results: Results of the FAHP indicated that safety and efficiency were the most important criteria. Results of the F-ARAS also revealed that increasing number of security personnel and training staff were the best recommendations for controlling violence against HWs. Conclusion: Based on expert\u27s opinions, administrative measures are the optimal ways to control violence at health centers; therefore, it is suggested that violence control programs should be more focused on administrative measures. Implications For Nursing Management: These results could assist nursing management to take best strategies for controlling occupational violence based on multi-criteria decision-making methods

Effects of storage duration and conditions on mechanical properties of Viola cucumber fruit under compression loading

In this research, the effects of storage duration and storage conditions on mechanical properties of cucumber fruit (Viola variety) were evaluated at different positions of the fruit length.  The cucumber fruit mechanical properties determined in this study were firmness, apparent modulus of elasticity, failure stress, failure strain and failure energy.  The mechanical properties determined under compression loading using puncture and uni-axial compression tests.  The results showed that the storage duration, storage conditions and fruit test position had significant (P<0.01) effect on the mechanical properties of Viola cucumber fruit.  The samples firmness, modulus of elasticity, failure stress and failure energy reduced about 49%, 39%, 38% and 33%, respectively during shelf life.  The failure strain of samples increased 18% during storage time.  Changing the mechanical properties of the cucumber fruit at room conditions was faster than refrigerator conditions.  The mechanical properties were differed along the length of cucumber fruits so that near the stem region of cucumber fruit had the maximum value of firmness, modulus of elasticity, failure stress and failure energy.  The sample failure strain had the minimum value at near the stem region of cucumber fruit.  Among the mechanical parameters that were evaluated in this research work, the firmness can be considered as the most appropriate parameter to evaluate textural properties of Viola cucumber fruit due to significant effect of independent parameters on it and ease of usage

Optimal Planning of On-Grid Hybrid Microgrid for Remote Island Using HOMER Software, Kish in Iran

HOMER software functions as a tool for modeling and optimization of an energy generation micropower system based on renewable technologies. In this paper for the first time the monthly real load data have been used in HOMER to design a renewable-based microgrid in grid-connected mode for Kish Island, Iran. The calculations were performed in a way that the designed system could supply the load demand of the studied area with the lowest cost, least pollution, and highest reliability. To overcome the intermittency of renewable energy sources such as wind and solar, a combination of these sources in a hybrid system and installation of battery storage systems were considered. The solar radiation and wind speed data required by the software were obtained from the country’s meteorology and NASA website and used in the software. The analysis results of four scenarios, including national grid/diesel generator, national grid/diesel generator/solar cell, national grid/diesel generator/wind turbine, and national grid/diesel generator/solar cell/wind turbine, showed the prices per kWh of $0.483,$0.505, $0.472,$0.537, respectively. In these scenarios, the share of renewable energies was 0%, 8%, 11%, and 26%, respectively. The highest amount of electricity sold to the national grid was 1597095 kWh/y for the fourth scenario which had also the lowest rate of CO2 emissions by 4128650 kg/y

Influence of the Inherent Safety Principles on Quantitative Risk in Process Industry: Application of Genetic Algorithm Process Optimization (GAPO)

Inherent safety (IS) refers to a set of measures that enhance the safety level of processes and equipment, rendering additional equipment and/or add-ons. The early design phase of processes is suited best for implementation of IS strategies as some of such strategies either are impossible to be implemented at the operation phase or substantially increase costs. The purpose of this study is to present a new approach called genetic algorithm process optimization (GAPO), by which processes can be made inherently safer even at the operation phase. This study simulates the IS principle, assessing its impact on quantitative risk and the possible consequences of process incidents identified by Hazard and Operation Study (HAZOP). The principle of intensification was simulated through GAPO, and feasibility of implementation was approved by HYSYS. Moreover, the integrated inherent safety index (I2SI) was used to evaluate and quantify the level of IS following implementation of GAPO compared to the initial design. Our result shows that GAPO substantially reduced the risk of consequences and quantitative risks and concomitantly improved the I2SI. The proposed GAPO can be applied to process operation as an approach to enhance IS at no cost and without decrease in production

Assessment of Aloe Vera for Qualitative Fit Testing of Particulate Respirators: A Logistic Regression Approach

Fit testing procedure is required for filtering facepiece respirators (FFRs) to ascertain an acceptable fit between the skin and facepiece sealing surface. The present study seeks to compare the efficacy of Aloe vera (A. vera) and commercial BitrexTM as challenge agents of qualitative fit testing of particulate respirators. An herbal solution consisting of A. vera at seven different concentrations was developed. Threshold Screening Tests (TSTs) of A. vera solutions were compared to BitrexTM. To do so, solutions were administered randomly on a total of 62 participants. A placebo was also tested to ensure the taste response being valid. Statistical analysis was performed using R 3.2.5.0 software. There were no statistically significant differences between the A. vera (41.7, 58.3, 75, and 91.7 mg/ml) and BitrexTM threshold tests. Therefore, the minimum concentration of A. vera to develop the threshold solution was considered to be 41.7 mg/ml. When commercial products are expensive and unavailable, a cost-effective technique would be to replace A. vera solution with a commercial product as a challenge agent of qualitative fit testing of respirators

Occurrence and Fate of Amoxicillin and Penicillin G Antibiotics in Hospital Wastewater Treatment Plants: A Case Study – Gonbad Kavous, Iran

Release of antibiotics to the environment as a result of wastewater effluent discharge is a cause for concern worldwide, as they pose a potential threat to  human health and the earth ecosystem. Penicillin and amoxicillin are widely used antibiotics. Despite their rapid hydrolysis in aqueous matrices, their  presence in the environment is widely investigated. The current study reported and analysed the current state of four hospital wastewater treatment  plants (WWTPs) in Gonbad Kavous, Iran, during 2019, from the perspective of amoxicillin and penicillin G removals. WWTPs were sampled at various  stages of the treatment process to determine at which stage the antibiotics are being removed. Concentrations of amoxicillin and penicillin G in raw  wastewater, analysed by HPLC, varied from 0.35 to 1.02 and 0.02–0.31 μgL−1, respectively. These values reduced in the final effluent, corresponding to  overall efficiency in removing the studied antibiotics of 20-60.5%. Anaerobic processes (i.e. septic tank) slightly outperformed aerobic biological processes  for both antibiotics’ removal, and penicillin G was removed more efficiently than amoxicillin. Effects of wastewater physicochemical properties,  including chemical oxygen demand (COD), biochemical oxygen demand (BOD), and total suspended solids (TSS) on antibiotics removal, were  also studied. Whereas statistically significant correlations were noticed between COD, amoxicillin and penicillin G removals, their decline showed no  correlation with TSS removal. Our study shows that despite the deployment of treatment plants, a considerable amount of antibiotics is released into  receiving water bodies, resulting in significant amounts of these pharmaceuticals entering the environment. There is abundant room for further progress  in the detection and quantification of pharmaceuticals and other emerging contaminants in hospital wastewaters and their metabolites and  biodegradation products.&nbsp