فهرست مطالب zabiolah damiri

Workload is one of the most important factors leading to the occurrence of work‑related injuries that can have impacts on quality of working life (QoWL). Therefore, the purpose of this study was to compare workload and QoWL in shift and nonshift workers of a water and wastewater contracting company.

In this  cross‑sectional study, workload and QoWL for all workers of a water and wastewater contracting company were investigated. Fifty‑one shift workers and 38 daytime workers completed NASA Task Load Index (TLX) as well as QoWL Scale by Van Laar et al. The data were analyzed by R software.

The results showed that physical demands of NASA‑TLX in shift workers were higher than those in daytime ones. Among the dimensions of QoWL Scale, only the difference between the average scores for home–work interface was significant in a way that the conditions for the group of shift workers were more favorable.

The results of this study showed that the volume of work and the quality of work in shift and nonshift workers are not significantly different and One reason is that the shift group had 12 hours more work and 24 hours more rest. The correlation between the dimensions of workload and QoWL demonstrated that increased workload would lead to a decline in QoWL.

Mental workload is an important issue in occupational health. This study aimed to determine the validity and reliability of the Rating Scale Mental Effort (RSME), Integrated Workload Scale (IWS), and Overall Workload Scale (OW) in Iran. This study was conducted on 100 male students of Iran University of Medical Sciences. The forward-backward translation method was used to evaluate the linguistic validity of the scales. Then the scales were presented to six ergonomics and occupational health experts to assess the content validity of the scales. Internal validity of the scales was assessed by correlating mental workload scale scores with reaction times on a criterion task. Finally, multiple sessions of a hybrid memory-search task were performed to determine the reliability of the scales. There was prefect agreement among the experts regarding of all three scales. Content Validity Index and Content Validity Ratio were 1 for each three scales. About the reliability of the scales, the Pearson correlation coefficients between the scale scores in the test and retest phases were 96, 88, and 84 for RSME, IWS, and OW, respectively. Finally, Validity and reliability of the scales were approved and It seems that these scales can be used for measuring self-reported mental workload.

clean room is an environment fully enclosed where parameters such as airborne particles under control and is requirement in the pharmaceutical industries to produce quality products. The aim of this study was to assessment and simulation of airflow and particle of clean room by CFD method in a pharmaceutical industry.
This study used an experimental study that was conducted at 2015 in the pharmaceutical industry. The methodology used in this study was to evaluate the level and number of particles in the clean room according to the standard ISO 14644 – 3. Also, air flow and particle in cleanroom with cleanness of class C was simulated with Computational Fluid Dynamics.
The results showed that the path of particle movement and distribution of particles in the clean room completely depend on the shape of the flow and the pattern of air flow in the clean room. Furthermore, the results of the simulation showed that the particles in the clean room wall return particle removal efficiency of 70% at 0.5 and 5 microns.
There is equipment and a tool in a clean room effects on the airflow pattern. The results of simulation showed that the pattern of dispersion, air flow in the clean room is the most affected by the removal of particles.

The clean room is under the control of concentrations of airborne particles play an important role in the production of drugs and high-tech products. Clean air flow pattern in the room is one of the important parameters of particle concentration and distribution of air pollution and need to be accurately modeled. So in this study was to evaluate and simulate the flow pattern of clean air in the room was investigated.
This study used an experimental study that was conducted at 2015 in the pharmaceutical industry .The methodology used in this study was to determine the air flow pattern in cleanroom. In this study, 3 clean room with 3 cleanliness classes B, C and D were studied. Then simulate the flow pattern, determine the velocity vectors in the cleanroom is cleared by CFD techniques.
The findings of this study showed that air flow rate measured in experimental models with air flow rates predicted by FLUENT software under the same conditions and at the same spacing is very close to each other .Also airflow velocity contours for 3 the cleanliness class were determined .In addition, the results of measurement of particle concentration in clean rooms shows the mean concentration of particulate contamination in three classes cleanliness was below the standard limit.
This study showed that RNG K-ℇ turbulence model the most appropriate model to simulate air flow pattern in the room is clean. There is also equipment and a tool in a clean room on the pattern of air flow and ultimately affects the particle removal efficiency in the clean room.

Nowadays, cleanrooms have become impartible parts of an industry with sensitive products. Sources of contamination in cleanrooms are impaired performance and quality sensitive products in the cleanrooms .The aim of this study was to evaluate the efficiency of HEPA filter and check the concentration and number of airborne particles in cleanrooms for pharmaceutical industry.
This study an experimental study that was conducted at 2015 in the pharmaceutical industry. The method of this study investigated the HEPA filter leakage test and number concentration of particles in the cleanroom according to the ISO 14644 – 3 standards .17 HEPA filters were studied for cleanroom with cleanliness class B, C and D. The leakage filters using aerosol photometer, aerosol generator and Positive injection pump and the Particle Counter was used to measure the concentration of particles.
In HEPA filter leakage test, 17 filters have been tested and only 3) 18 %( filters indicate leakage and had an efficiency lower than standard limits. Other filters had a no leakage and show acceptable results (99.99%). The results show that with increasing velocity, permeability and pressure drop in the range of particle size increased and decreased quality factor. In addition, the measurement results show that the concentration of particles in the cleanroom the average density of particles pollution in the cleanliness class B, C and D of the ISO-14644 standard limits was lower.
the study showed that the airborne particles concentration are lower than the permissible limits which determined by ISO 14644 standards. Interestingly in this study, the impact of high air quality cleanroom was a good performance HEPA filters.

Nowadays, many modern industries require an environment with no contamination by particles and bacteria. An enclosed clean room environment is a place where parameters such as airborne particles, temperature, humidity, air pressure and air flow pattern is controlled. The aim of this study was to evaluate functional parameters of a clean room in a selected pharmaceutical industry.
Material and This study was an experimental study conducted in 2015 in a pharmaceutical industry. The air flow rate and flow rate with airflow capture hood was used and multi sensor devices for measuring temperature, humidity and pressure of multi-sensor device. HEPA filter leakage test and counting concentration of particles in the cleanroom was done according to the ISO 14644 – 3(2005) standards using aerosol photometer and aerosol generator. In this study, 6 clean room relating to the 3 cleanliness classes B, C and D (in accordance with standard EU GMP) were evaluated. Meanwhile, both the 2 and 3-dimensional flow model using Computational Fluid Dynamics Software was simulated in this study.
Measuring the parameters flow rate and air velocity, temperature (average temperature 20 ° C), relative humidity (below 50%), pressure (pressure less than 15 psi) for every three classes of cleanliness are all acceptable and less than the proposed standard. Furthermore, the results of modelling showed that the pattern of air flow in the room is correct paths in circulation. In the case of leakage test filters, the filter 29 filters tested 5 was leaking and ultimately determine the HEPA filters remove particles that average efficiency is 99.99%.
This study showed that the high volume and good quality of air entering the clean room affect the optimal efficiency and air flow rate, pressure drop and air penetration of the HEPA filters Also, the results of study show that the concentration of airborne particles in clean room is depend on the air flow rate and speed and adopting a good air flow pattern will affect the particle concentration.

High mental workload is one of the important factors that results in errors in safety and occupational health scope and its measurement has high importance. So, this study aimed to determine validity and reliability of Verbal Online Subjective Opinion (VOSO) and Modified Cooper-Harper (MCH) scales in measuring mental workload.
This study was conducted on 90 male students of Iran University of Medical Sciences. In this study, the Forward-Backward translation was used for translation of scales. Moreover, Content Validity Ratio (CVR) and Content Validity Index (CVI) were calculated by having suggestion of 6 Ergonomics and Occupational health experts. The Hybrid Memory Search Task software was used to create mental workload. Convergent validity of scales was calculated using correlation of scales with reaction time and then Test-Retest method was used to determine the reliability of scales.
Content and convergent validity of scales were confirmed and correlation of both scales with reaction time were higher than 0.8. Moreover for determination of scales reliabilities, Pearson correlation coefficient between scales values in test and retest trials were 0.86 and 0.91 for VOSO and MCH respectively.
It seems that in regard to confirmation of validity and reliability of VOSO and MCH in this study and their high correlation with reaction time, it can use these scales in measurement of mental workload.