Journal of Health and Safety at Work

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Introduction: Lead exposure is considered as a global health problem. The irreparable harmful effects of this heavy metal on human have been proven in various studies. Comparing to general population, workers in related industries are more exposed to lead. Several studies have investigated lead occupational exposure and its biological evaluation in Iran; however there is no overall estimate. Thus, the present study was conducted to determine the occupational exposure to lead and its biological evaluation in Iranian workers, using systematic review and meta-analysis.

Material and Method: This study was carried out based on information obtained from databases including Magiran, Iranmedex, SID, Medlib, Trials Register, Scopus, Pubmed, Science Direct, Cochran, Embase, Medline, Web of Science, Springer, Online Library Wiley, and Google Scholar from 1991 to 2016, using standard key words. All of the reviewed papers which met the inclusion criteria have been evaluated. Data combination was performed according to Random Effects Model using Stata software version 11.1.

Result: In the 34 qualified studies, the mean blood lead level (BLL) concentration in Iranian workers was estimated 42.8µg/dl (95% CI: 35.15-50.49). The minimum and maximum BLL were belonged to west (28.348µg/dl) and center (45.928µg/dl) regions of Iran, respectively. Considering different occupations, the lowest mean value was reported in textile industry workers (12.3 µg/dl), while the highest value was for zinc-lead mine workers (72.6 µg/dl). Mean breathing air lead level of Iranian workers reported in 4 studies was estimated 0.23 mg/m3 (95% CI: 0.14-0.33).

Conclusion: According to the high concentration of BLL and breathing air, it is recommended to increase protective measures and frequent screening. Scheduled clinical and paraclinical examination should also be performed for workers.

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Introduction: Cranes are of the major causes of accidents in the construction industries. As human error mostly causes crane accidents, this study aims to investigate the human errors of tower crane operators in the construction projects using SHERPA and CREAM techniques.
Material and Method: In this research, first, all of the tasks of the tower crane operator were identified and analyzed. Then, adopting SHERPA technique, probable operator errors were identified in each task and the control modes and error probability were determined by CREAM technique. Finally, all the human errors risks were assessed and the actions for risk control were defined to control them in the acceptable level.
Result: According to the SHERPA technique, 148 errors were identified in the crane operator tasks. The human error assessment showed that monitoring the anti-collision system with the risk probability of 0.0003 has the highest control factor, while monitoring the existing guards with the risk probability of 0.056 has the lowest control factor. Also, the important tasks with high human errors were monitoring the guards with the cognitive risk probability of 0.07 and the tasks with cognitive risk probability of 0.05.
Conclusion: The findings in this study indicated that using complementary qualitative and quantitative methods can provide identification and prioritization of identified errors. This can help the organization   to allocate limited organizational resources to control unacceptable risks and increase the efficiency and effectiveness eventually.

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Introduction: Each country needs to preserve its human capital through preventing accidents for its development. Therefore, this study is carried out to study the relationship between safety investments and safety performance indices considering the interactive effect of the project hazard level in construction industry.
Material and Methods: This study was conducted using multiple case studies in 5 major construction worksites, in Tehran, in 2019. Data was collected using questionnaire, checklists and interview as well as evaluating the safety documents. The data analysis in this study was carried out using SPSS 18.
Results: There was a strong inverse correlation between safety investments (total safety investment, basic safety investment, and voluntary safety investment) and accident frequency rate (AFR) (r=-0.936, P-value<0.05), and there was a direct strong correlation between safety investment and safety performance (P-value<0.05, r=0.939). Also, the effect of various safety investments on safety performance indices under various project conditions (project hazard levels) was not the same; when the project hazard level was high, the effect of safety investments on safety performance was higher.
Conclusion: Increasing safety investment improves safety performance through decreasing the accidents. Also, investment in both safety components (basic safety investment and voluntary safety investment) might improve safety performance. The results of the current study can be used as a basis by the contractors and construction companies to invest in safety and to determine proper budget for managing safety of construction projects.

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Introduction: For years, chemical process industries have reported the unexpected release of highly hazardous liquids and gases. A disaster could not be avoided when these materials were not adequately controlled. The issue of Process Safety Management (PSM) is still being discussed in developing and developed countries. PSM was established to manage the risks of a company’s personnel, properties, products, environment, and credit risks. This study aimed to review the challenges and achievements of PSM implementation and provide recommendations for improvement.
Material and Methods: A collection of scholarly articles published from 2000 to 2023, such as Science Direct, WOS, PubMed, and Scopus, was chosen through a systematic, meticulous review. After thoroughly examining these abstracts, titles, and complete contexts, 49 articles were finally selected for inclusion in the study and classified based on different criteria, such as publication year, authors, achievements, and challenges.
Results: PSM in the United States has been chiefly studied due to the high number of chemical process industries and its presence in the form of OSHA legislation in this country. The areas of operations, audits, and resources have the most challenges in implementing PSM. On the other hand, reducing the severity of incidents in chemical processes and increasing productivity are considered the most significant achievements of PSM implementation.
Conclusion: PSM as an interdisciplinary field has improved  and become more effective over the years.. However, incidents still exist, and the number can increase, considering the growth of industries’ chemical processes. Therefore, a deep look at the issues of risk-based regulations, competency, operational excellence, and learning from incidents is necessary to achieve excellence in PSM.

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Introduction: Hospitals represent a critical fire safety challenge. The presence of patients with limited mobility, specialized staff, and invaluable infrastructure makes them seriously vulnerable. Further, toxic smoke inhalation, as a primary product of fire, is a leading cause of mortality. To address this concern, our study intended to conduct a comprehensive fire safety assessment of a teaching hospital in Tehran (2023-2024) by integrating risk assessment with numerical modeling.
Material and Methods: This study was conducted in a teaching hospital following three consecutive steps: risk assessment, fire scenario design, and fire and smoke modeling. First, vulnerable zones were identified using the FRAME method. Next, fire scenarios and control strategies were designed based on the identified risk factors and a review of the relevant literature. Ultimately, fire and smoke transport was modeled using the CFAST software to ascertain the performance of the proposed strategies.
Results: The risk assessment pinpointed two wards with unacceptably high occupant risk levels: the inpatient ward on the 10th floor, owing to a cluster of unsafe behaviors, and the basement warehouse, owing to improper storage and inadequate emergency exit access. Fire and smoke modeling was performed for these two zones, comparing the “current situation” against a proposed “risk control strategy.” The modeling results revealed that the control strategy positively affected key life safety indicators, significantly ameliorating the Fractional Effective Dose (FED) and Heat Release Rate (HRR).
Conclusion: According to this study, a fire risk assessment provides a clear and detailed perspective on a hospital building’s fire safety. Integrating the results of the FRAME assessment with CFAST simulations results in a comprehensive understanding of the facility’s safety status. These data can be utilized to design effective emergency plans and calculate the Required Safe Egress Time (RSET), thereby preventing life-threatening harm to occupants against toxic gases.