Archives Of Occupational Health
Volume:7 Issue: 1, Jan 2023

he Indoor Environmental Quality (IEQ) affects physical-mental health and well-being of people. Lighting, air quality, thermal comfort, and acoustic comfort are the most crucial factors in IEQ, directly influencing the quality of life (1).
     The significance of IEQ has gained public attention in recent years, primarily due to the impact of global climate change and the emergence of green building designs (2). The adverse effects of climate change have adversely affected the habitability of public spaces, thereby necessitating the adoption of design and technical measures to improve the well-being and health of low-income communities (3).

A small fire in process industries such as refineries and petrochemicals can cause a domino effect and spread to nearby units. These industries include many processes such as production, storage, and transfer, which are different in nature and have different risks from each other. The domino effect causes the spread of the accident in the adjacent units using escalation vectors. Domino events are mostly very low frequency with severe consequences. Therefore, special attention should be paid to their prediction and control. The consequences of these accidents are diverse at different levels and besides industrial sites, they also affect people, the environment, and the economy. Therefore, the effects of these accidents are recognized as an important priority issue among risk experts and the safety community, for example, the EU requirements in the Seveso-II directive (1). A noteworthy point about most of the process accidents inside the country (Iran), such as the petrochemical accident in the Bouali Sina reservoir, was that they happened in a domino pattern (2).
Therefore, during risk analysis and assessment, it is not only important to deal with one equipment or unit, but the chain effects of the accidents of that equipment or unit on other units should also be considered, and this can be done by examining the domino effects of accidents. A domino system consists of at least two source and target subsystems. The domino effect has several basic components:
The initiator of the domino effect, which is the initial event, is often fire and explosion. The possible causes of these events can be a combination of human, process, and organizational management factors. This can be achieved by using Root Cause Analysis (RCA) approaches such as Fault Tree Analysis (FTA), and Fishbone. Natural disasters in industrial environments (Natural Hazards Triggering Technological Disasters: Natech) and terrorist attacks are other possible causes of an initial event. In the study of Taveau (2011), 206 incidents that occurred continuously in floating roof tanks were investigated, of which 145 incidents were fires and 61 incidents were explosions (3). According to Kletz et al.'s study, the main causes of accidents in these tanks were lightning (32%), maintenance operations (13%), operational errors (12%), equipment failure (8%), sabotage (8%), cracking and rupture (7%), pipe leakage and rupture (6%), static electricity (5%), open flames (4%), natural disasters (3%) and runaway reaction (2%) (4).
Escalation vectors that are responsible for the possible spread of the accident. Escalation vectors are physical effects such as thermal radiation, excessive pressure, or fragments thrown by explosions. Escalation vectors depend on various factors, such as the type of initial event and the distance between the center of the event and neighboring units.
Secondary random events can happen from one to several.
A final consequence that is much more severe than the consequences of the initial event. The domino effect is a sequence of successive reactions, the result of each reaction can be to strengthen the result of the previous reaction.

There are several methods for calculating escalation vectors, including analytical models, integral models, and average models, which are a combination of two analytical and integral models (2). To determine which units are affected, the initial vectors applied to the adjacent units as a result of the initial event should be compared with the predetermined threshold values. If the escalation vectors are significantly higher than the corresponding threshold, it means that they have enough power to damage the adjacent units, which itself leads to the loss of safety or physical integrity. Therefore, a preliminary screening of the neighboring units is done by doing this comparison, and potential secondary targets are identified. Potential secondary units are those adjacent units that are more likely to participate in the domino effect. The presence of secondary units in the domino effect not only aggravates the accident and the consequences but also causes the domino effect to be promoted to a higher level by affecting the third unit. The escalation vectors caused by secondary events also lead to the occurrence of other events at the third level. Therefore, more attention in this field will improve the safety culture to prevent these accidents. The definition of student theses and their practical implementation in industries can be one of these cases.

Noise pollution is a serious issue in hospitals, especially in emergency departments where high noise levels from emergency patients and treatments can negatively affect medical personnel and patients. This study aimed to measure noise levels during day and night shifts in three major hospitals affiliated with Tehran University of Medical Sciences (Imam Khomeini, Shariati, and Sina hospitals) and investigate the level of annoyance experienced by medical staff.

In this cross-sectional studyTES-1351B sound level meter was used to measure sound pressure levels and the measurement stations were determined according to ISO 9612 standard. A general questionnaire was used to determine demographic characteristics. Also, by a valid self-reporting questionnaire, the feeling about environmental noise intensity and noise annoyance was measured. Statistical analysis was done by SPSS software using ANOVA and t-test.

The average sound pressure level in the emergency departments of the studied hospitals was 67.940±7.70 dB. Significant differences were found between morning and evening shift noise levels. (p-value=0.001). The highest average sound pressure level occurred during the evening shift with an average of 72.382±4.35 db. Also, there was a significant difference between the feeling about environmental noise intensity and noise annoyance in Imam Khomeini and Sinai hospitals respectively, (p-value=0.037) (p-value=0.011).

The study concludes that noise pollution in the emergency departments of these hospitals needs attention. Implementing administrative and technical-engineering measures to reduce noise pollution is essential to enhance the well-being of medical staff and patients and ensure a more satisfactory healthcare environment.

Healthcare workers (HCWs) need to perform new preventive measures to protect themselves and patients against ongoing COVID-19 transmission, which can increase hand dermatitis (HD) among them. This study aims to investigate the prevalence of HD among HCWs and its possible risk factors in IRAN.

A survey of 159 HCWS working in university hospitals was performed from August to September 2020 in a cross-sectional study. Research data were collected via standardized self-administered questionnaire. The history of HD was determined via standardized Nordic Occupational Skin Questionnaire (NOSQ-2002).

The prevalence of HD in the study population was 51.6%. A significant association was found between the prevalence of HD among HCWs and sex, age, working hours per week, and wearing gloves (P<0.05).  Females had a 3.84 fold higher risk of HD than males (confidence interval (CI): 1.85-8). HCWs older than 40 and those who aged 30-39 had a 9.6 and 1.72 fold higher risk of HD than those aged 20-29 (CI: 2.6-35.7; CI: 0.87-3.4, respectively).

Possible risk factors for developing HD among HCWs are female gender, age, wearing gloves, and fewer working hours per week. Preventive measures for HD are needed for HCWs, especially during the COVID-19 pandemic.

Nowadays, a large proportion of work-related activities are performed manually, which has led to an increase in the prevalence of musculoskeletal disorders (MSDs). This study aims to assess the risk of manual material handling (MMH) and estimate the prevalence of MSDs among workers in rice mills in the northern part of the country.

The study was conducted on 100 workers employed in 36 rice mills in Gilan Province using the census method. The Nordic questionnaire was used to determine the prevalence of musculoskeletal disorders, while the NIOSH equation, Snook table, KIM-LHC and MAC assessment methods were used to evaluate the risk of related activities. Data were then analysed using chi-squared test and Spss23 software.

The results of the KIM-LHC and MAC lifting methods showed a high prevalence of musculoskeletal disorders in the lower limb during lifting. Similarly, there was a statistically significant relationship (P=0.001 and P=0.002) between the Mac and Snook lifting methods. However, there was no significant relationship between the Niosh method and either the Kim-LHC or Mac-Lifting methods (P=0.10 and P=0.28).

The results of the risk assessment using different methods showed a consistent and critical condition of the working environment in the rice mills studied. Therefore, it is imperative to take the necessary engineering and management control measures to improve the working conditions.

This study was conducted with the aim of determining the impact of engineering, organizational and individual ergonomic interventions on the indicators of the percentage of workers complaining of musculoskeletal problems, having an inappropriate work station, exposure to inappropriate manual handling, and also the percentage of sick leave in workers of a rubber industry.

Materials and methods:

This is a descriptive-analytical and retrospective study that was conducted in the production department of a rubber manufacturing industry. Ergonomic interventions that have been fully implemented in the industry and have been stable were included in the study, and data were extracted by examining the documentation related to ergonomic assessment tools before and after each intervention. Before and after comparison of indicators was done using paired t and Wellcoxon tests.

Results:

 Ergonomic interventions included 114 engineering interventions, 20 organizational interventions and 7 individual interventions. Engineering interventions had a significant effect on all indicators such as in reducing total musculoskeletal problems  )66%). Organizational interventions  has led to the improvement of the index of musculoskeletal problems (60%), inappropriate posture (55%) and  pain intensity (30%). Individual interventions also had a significant effect on musculoskeletal problems (85.71%), pain intensity (42.85%) and sickleaves (100%) (P<0.05).

All three types of ergonomic interventions in the production sector of the rubber industry have been effective in reducing musculoskeletal problems. Engineering interventions have had a significant impact on all the health indicators considered in this study. Engineering interventions in the rubber industry are more effective and it is better to be implemented together with organizational or individual interventions to complete the effectiveness.