Journal of Health and Safety at Work
Year:2018 | Volume:8 | Issue:2 |Papers Count:8

Introduction: Anesthetic gases used in hospitals include N2O and halogenated hydrocarbons (such as sevoflurane) which can be released through leakages and uncontrolled exhalation by the patient into the ambient air of clinical staff. These gases have greenhouse effect and damage to the ozone layer and serious risks such as reproductive, preterm delivery and fetal abnormalities and increased spontaneous abortion on the health of operating room personnel. Therefore, removal of these gases from the workplaces is essential especially in the treatment centers. The purpose of the present study was to investigate the adsorption of sevoflurane from air by using activated Charcoal and also the effect of acid modification on its performance.Material and Method: In this study, two adsorbents of unmodified and modified activated charcoal with nitric acid were used to remove sevoflurane. After preparation, the adsorbents were characterized using XRD, FT-IR, BET and FE-SEM methods. After characterization, the breakthrough and adsorption capacity of sevoflurane on both adsorbents were determined using the modified wheeler equation.Result: The results of characterization showed that acid modification did not affect the crystalline structure of activated charcoal and increased the adsorption and microporous of acid-modified activated charcoal in comparison with unmodified activated charcoal. It also reduces surface functional groups of the activated carbon. The results of determination of adsorption capacity indicated that the adsorption capacity of modified activated charcoal was improved in comparison with unmodified activated charcoal.Conclusion: The results demonstrated that both adsorbents have the ability to absorb sevoflurane and modified activated charcoal have a better performance in this process. This effect may be due to the surface area of adsorption and volume of micro pores more than the unmodified activated charcoal.

Introduction: Impairment of alertness, attention and performance associated with sleepiness and fatigue in nurses occur in night and long-term shifts that in the end of night shift reach to the maximum level can lead to traffic accidents when they returning home. The purpose of this study was to determine the effect of night shift on psychomotor abilities of driving in nurses after shiftwork.Material and Method: A cohort study was carried out on 23 night shift and 24 day shift female nurses aged 20 to 40 at Sina Hospital in Tehran city, using the Vienna Test System (VTS). The concentration and selective attention, reaction time, pheriperal perception, and coordination before and after night and day shifts were measured. A multiple linear regression model and Backward stepwise selection method was used for analyses.Result: In the concentration and selective attention test, sum hits (p= 0.038) and in the visual perception test, divided attention (p =0.006) and visual field (p=0.019), and in the reaction time test the mean motor time (p=0.034) showed a significant adverse relationship with working in night shift, but the visomotor coordination variables did not show any significant correlation.Conclusion: The results showed that the concentration and selective attention, peripheral perception, and reaction time of psychomotor ability of driving were significantly adversely impaired in nurses after night shift. These results in evidence of the mechanism of increasing traffic accidents after night shift among nurses added to the previous studies in this subject.

Introduction: The Surgical Safety Checklist has been introduced by the World Health Organization (WHO) as a tool for reducing medical errors. Reviewing the results of the checklist application indicates significant reduction in mortality and complications in surgery. Thus, this study aimed to customize and validate surgical safety checklist in order to complying with the surgical protocol in Iran.Material and Method: In this cross-sectional and descriptive study, the WHO Safety Surgery Checklist was first translated. Next, through interviews with specialists and direct observation of activities, those tasks that were susceptible to the incident, identified, prioritized and analyzed using Hierarchical Task Analysis (HTA) and the results presented in form of HTA charts. Then, using Tabulate Task Analysis (TTA) and based on the recommendation and modification commented by expert panel, some questions added to the checklist and a customized version of the Surgical Safety Checklist was provided. Hence, the faced validity, content validity and reliability of the checklist have been evaluated.Result: In the surgery, four major tasks identified f or analyzing u sing the H TA c hart. Accordingly, 4 1 subtasks obtained and analyzed by TTA. The Lavashe method was used to determine the content validity ratio (CVR) and the content validity index (CVI). The question from the checklist, in which, CVI was less than 0.79, modified and replaced with appropriate question. Also, the scores for 3 questions were less than 0.49, and they were removed from the checklist due to the low CVR score. In the reliability assessment, the intra-observer method is used, and the Kappa coefficient obtained was acceptable and it was higher than 0.6, which confirmed the validity of the checklist.Conclusion: In this study, the surgical safety checklist customized in terms of content validity and reliability, in a field study. Considering the compliance of the checklist items with the surgical protocol in Iran, we hope to use it to improve the quality of teamwork and reduce the complications and mortality caused by surgical errors.

Introduction: Using diesel generators is necessary for activities like welding in construction sites and it is often accompanied with noise pollution. The aim of this study was to evaluate noise pollution induced by diesel generators in construction activities in one of the districts of Tehran city.Material and Method: In this descriptive study, 14 construction sites were selected for the evaluation of noise pollution in Tehran, district 4. Background and diesel generators sound pressure level were measured in accordance with BS 5228 (2015) and noise guidance in the area around the construction sites. Diesel generators sound pressure level at 4 points and also the audio frequency analysis, one meter away from the device was measured at a random locations around it. TES-1358, Type 2(Taiwan) sound level meter was used to measure sound pressure level and calibration was performed before and after noise measurement. The validated Noise annoyance questionnaire adopted from ISO15666 standard, completed by the residents. T test, correlation and analysis of variance was performed to analyze data using SPSS software ver. 22.Result: The mean equivalent sound level of diesel generators background noise were respectively 76 ± 4.05 dB (A) and 46.2±1.09 dB (A) around the construction sites. Diesel generators noise around the construction sites was higher than the noise limit (background noise plus 5 dB) (P Value <0.05). The highest (95.3±0.33 dBA) and lowest (90.9±0.63 dBA) average sound pressure level was related to Benz355 and Perkins generators. One-way ANOVA statistical analysis showed significant differences in the average sound pressure level of various diesel generators between the devices (P Value <0.05). The mean sound pressure level among 190 sound monitoring stations in the interior parts of the construction sites were about 81.11±4.6 dB(A). The experienced noise annoyance was evaluated higher than the average by 73.4 percent of residents. Residents’ noise annoyance and noise level around construction sites were significant using Pearson correlation (R=0.486, P value <0.05). Dominant noise frequency and associated sound pressure level of diesel generators were measured 63 Hz and 84.4 dBA, respectively.Conclusion: Diesel generators noise in the area around the construction sites was higher than the environmental noise limit and it was accompanied with abundant noise annoyance for residents around these construction sites. Therefore, due to the lack of environmental rules related to construction industry noise pollution in Iran, assessment and approving of such rules is essential to reduce noise annoyance in urban areas.

Introduction: Heat stress is one of the hazardous agents in the steel industries which can threaten the health and safety of workers and lead to serious occupational diseases. The aim of the study was to assess the heat stress in the steel industries and compare PHS (Physiological Strain Index), WBGT (Wet-Bulb Globe Temperature), DI (Discomfort Index) and HSI (Heat Stress Index) indices for the estimation of heat stress and to determine the optimum index for steel industries.Material and Method: This descriptive-analytic study was conducted among 220 workers engaged in two steel industries in Iran. Environmental and physiological parameters were measured according to ISO 7726 and ISO 9886 in three times of measurement, and finally the time-weight average of the heat stress indices were calculated. All data were analyzed using SPSS ver. 20.Result: The time-weight average of WBGT (28.28oC), DI (29.11oC), HIS (65.7 %) indices were higher than the recommended limits. Physiological parameters (oral, tympanic and skin temperatures, systolic and diastolic pressures and heart rate) had the greatest value in the second time of measurement (afternoon). WBGT index comparing to the PHS, DI and HSI indices had highest correlation with oral, tympanic and skin temperatures and heartbeat (r=0.314, 0.408, 0.459, 0.302, respectively; P<0.05), while systolic and diastolic blood pressures showed no significant correlation with WBGT (P>0.05). The WBGT index had the highest correlation with studied indices which was 0.945, 0.681 and 0.600 for DI, PHS and HSI, respectively.Conclusion: This study assessed the optimal index with regard to the physiological parameters, and it was concluded that the WBGT index has the highest correlation with the most of physiological parameters, and therefore, WBGT index can be the most optimum index to heat stress assessment in the studied steal industries.

Introduction: There are some tensions in occupational activities that are caused by harsh conditions and occupational violence is considered one of these tensions. Workplace violence is a global problem. Healthcare workers are globally exposed to the workplace violence more than any other workers. The aim of this study was to investigate the relationship between some individual and job variables with exposure to occupational violence among health care workers in the hospitals in Yazd province, Iran.Material and Method: This cross-sectional, descriptive-analytical study was conducted in eight educational hospitals in Yazd province, Iran. Research population (600 participants) consisted of all healthcare personnel employed in hospitals affiliated to the Shahid Sadoughi University of Medical Sciences in Yazd and were selected by stratified sampling. The Negative Act Questionnaire-Revised (NAQ-R) was used to investigate occupational violence and data analysis was performed using multiple logistic regression tests.Result: The average score of occupational violence was 19.3. Among individual factors, gender (male) and educational level (MSc degree), and among job factors, shift work (morning shift) and type of work environment (genecology and pediatrics wards) had significant relationships with the incidence of violence among the employees. Conclusion: The importance of these findings is in planning and deployment of intervention measures using educational training with regard to the ways of preventing violence, decreasing the coworkers’ aggression, dealing with and increasing awareness about personal and civilian rights in order to reduce the phenomenon of violence among employees.

Introduction: Mercury, in different form can induce adverse effects on various organs especially central nervous system. The aim of this study was to determine concentration of mercury in inhalation and urine of the exposed worker and to investigate the prevalence of probable neurobehavioral disorders.Material and Method: The present case-control study was conducted among workers of a unit in a petroleum industry. The study population consisted of 52 workers as case and 63 workers as control groups. The mercury concentration in air and urine was measured according to NIOSH 6009 standard and using the cold vapor atomic absorption spectrophotometer (CV-AAS). Demographic data and neurobehavioral disorders were collected using a self-reported questionnaire. Pearson correlation coefficient, multiple regression tests and SPSS v24 were used to analyze the data.Result: Air concentration of mercury was 0.062 ± 0.0014 mg/m3 which was higher than the recommended threshold by NIOSH and ACGIH. In addition, there was a significant difference between urinary concentration of mercury in the case (37.73±13.01 mg/g cratinine) and control (5.93±4.76 mg/g cratinine) groups (p=0.03 6). Based on the multivariate logistic regression model, significant relationships were found between memory loss, sleep disturbance, and urine mercurial concentrations and, between memory loss, moody, muscle weakness and air mercurial concentration.Conclusion: The values of Hg in blood and urine workers who worked in investigated unit were significantly higher than recommended threshold values. In addition, the Hg concentration in urine was related to some of neurobehavioral disorders.

Introduction: Being aware of the explosion, fire radius, and their damages, has an important role in accident prevention methods. Therefore, the aim of this study was modeling and evaluation of the consequences of propylene oxide spill in a petrochemical company.Material and Method: The QRA method including seven steps was used in this study. In the present study, in order to examine and modeling of the propagation propylene oxide, first a familiarization with the process information of the unit was done then, a risk assessment was carried out adopting HAZOP technique to identify existing hazards. Consequence analysis in a process unit includes: selecting important scenarios, characterizing scenario, modeling the consequences of scenarios, analyzing the results and determining the percentage of mortality. PHAST software version 6.51 was used for modeling of outcomes and assessment propylene leak. Result: urves of the firing zones of sudden release of propylene oxide showed that the influence puts are included up to radius of 0.15 meters in the scenario of leakage 5 mm, in scenarios with leaks 25 mm to a radius of 1.1 meters and in scenarios with leakage of 100 mm to a radius of 39 meters. The maximum intensity of flash fire in the initial point Scenario 5 mm was 4.2 kW/m2, in the scenario of radiation leakage was 25 mm at the distance to 5 meters from the fire intensity up to maximum of 9 kW/m2, and also in the scenario with 100 mm flash fire radiation leak at an earlier point fire was 14 kW/m2. The maximum intensity of thermal radiation at the distance to 5 meters up to 16.5 kW/m2, and maximum distance of 80 meters around the reservoir affected. The mortality rate of flash fire has exposed employees, was 50 percent.Conclusion: Many accidents caused by leakage and explosion were due to corrosion, spoil tanks and equipment, and the majority of such accidents can be prevented by technical inspections and continuous audits.