International Journal of Occupational Hygiene
Volume:8 Issue: 4, Dec 2016

Control room is the heart of each system in which even a minor error can result in irrecoverable consequences. The purpose of this study was to determine the Probable Control Modes (PCMs) and Cognitive Failure Probability (CFP), and also build a Cognitive Demands Profile (CDP) in a petrochemical control room, using Cognitive Reliability and Error Analysis technique (CREAM). First, tasks of Boardman (B.M), Shift Control (S.C), and Head Control (H.C) in control room were analyzed, applying hierarchical task analysis. Following, PCM, CFP and CDP were determined for the analyzed tasks. According the results, control modes for the tasks of B.M and S.C were determined as opportunistic; while for H.C tasks it was obtained as tactical. Of the all error types, execution failure (48.57%), interpretation failure (18.57%), planning failure (15.71%), and observation failure (17.15%) were identified. The most important CDPs were communicate, monitor, execute, plan, diagnose, evaluate, co-ordinate, verity, record, and scan. Based on the findings, number of simultaneous goals, time of day and adequacy of training and experience in the study field were the Common Performance Conditions that led to reduction of performance reliability. These factors contributed to the opportunistic control mode. In order to prevent or reduce cognitive errors in the control room, we need to know the exact type of cognitive activities, and develop a comprehensive program to increase the knowledge and skills for performing the cognitive activities.

This study compared the sleep quality and sleepiness in day workers and shift workers. Sleep quality and sleepiness in staff nurses were significantly different than employees.
Shift work is an important factor influencing the sleep quality and sleepiness of nurses. The aim of the present research was to compare three groups: (1) nurses with shiftwork; (2) nurses without shiftwork as control group for evaluate the effects of shiftwork; and (3) regular non-shift employees who were not nurses as control group for nursing job and evaluate the effect of workplace and nature of nursing job (employees of Kerman University of Medical Sciences) with regard to their sleep quality, and to find the factors determining their sleep quality.
The present study was cross-sectional in design and was carried out in 2011. The research participants were 326 nurses (without shift work and with shift work) and employees of KMU University hospitals. Data in this study were gathered via the Pittsburgh Sleep Quality Index and Epworth Sleepiness Scale.
91.2% of nurses and 79.6% of employees had poor sleep quality. The sleep quality (p=0.013) and sleepiness (p=0.005) of hospital nurses (without shift work and with shift work) were significantly different from that of the university employees. However, there was not a significant difference between the nurses without shift work and nurses with shift work in terms of sleep quality (p =0.87) and sleepiness (p=0.41).
Job stress, daily average hours of sleep, and shift work are among the influencing factors causing sleepiness and poor sleep quality.

Driver drowsiness has been one of the main causes of on-road crashes which can lead to death, physical injuries and impose significant costs on the societies. The development of non-intrusive methods to be able to detect driver drowsiness in the early stages of drowsiness is great of importance. This is an educational review and its purpose is to provide recent achievements about non-intrusive techniques used to detect driver drowsiness. Recently published related articles were searched in the scientific databases such as Web of Sciences, Scoupous, Pubmed and Google scholar. By studying the articles and extracting the important information, non-intrusive drowsiness detection methods has classified in three distinct categories: Vehicle based measures, behavioral measures and non-intrusive physiologic methods. Each of mentioned categories has its own advantages and limitations. Vehicle based methods are strongly influenced by the road geometry, whether condition and lighting. By tracking the facial expression of the driver, drowsiness can be detected. The main limitation of this method is lighting, because the cameras do not function well at night. However, physiological parameters such as electroencephalography are more reliable than vehicle and behavioral measures, the intrusive nature of these methods limit their applications. In summary, combination of the mentioned method can reliably detect the drowsiness of the driver and further studies about the efficiency of the mentioned techniques in real environments are required.

The implementation of HSE programs is so complicated in tunneling industry which is considered as one of the risky industries. This study aims at investigating the relationship between employee's safety attitudes and status of their belief in destiny, chance and perceived importance of HSE programs in occurrence of occupational accidents.
This research is a cross-sectional and descriptive-analytical study on a contracting company specialized in tunneling, and investigates a total of 689 subjects. A standard 25-item questionnaire is used to assess safety attitude; and three researcher-made questions are utilized to evaluate the subject's belief in destiny, chance and perceived importance of HSE programs in occurrence of occupational accidents. The reliability and validity of these questions are obtained by Cronbach's alpha test (α=0.76). All analyses are done at the significance level of 0.05 by the help of SPSS 16 software.
There is a significant direct relationship between belief in chance in occurrence of occupational accidents with subject's safety attitudes (P-value According to the results of this study, the employees, who consider external factors such as chance and destiny as the main and absolute reasons for occurrence of occupational accidents, believe less in controlling accidents by looking for solution and scientific and educational methods such as prevention programs of HSE to cope with event.

Traffic accidents are one of the most important challenges of public hygiene that needs global attention and effort. The recent research was conducted in order to determine the crash trend and develop the accident prediction model that leads to death in Ilam from 2010 to 2014. The recent study based on Descriptive analysis was performed by using the statistical data related to death caused by driving accidents in Ilam during 2010 to 2014. In order to determine the related factors to accidental death during the years of interest, the time series was used and the ARIMA model was utilized for analyzing the time series. The data were analyzed by STATA 11.During the five years of study in this research, 21.3% of the dead people are female while the 78.7% are male from the aspect of gender. The results of time series model showed that among all considered variables there is a significant relationship between the type of passage way, the situation of a deceased person by car accident, accident type, and vehicle type, with.fatal accidents (P

Drivers are vulnerable to musculoskeletal and psychological disorders because of substantially harmful agents in this stressful occupation. This study aims to investigate the influence of driver’s physical and psychological health on the risk of road accidents using fuzzy logic approach.
Two input variables including musculoskeletal disorders (MSDs) and mental health, alongside accident risk levels as output variables were fuzzed using a fuzzy inference system (FIS). Triangular and trapezoid membership functions were used to graphically define outputs related to low, moderate, high and very high, in fuzzy sets. A mamdani-type FIS was applied to represent all the rules in the IF-THEN format and the patterns of linguistic variables were designed using AND, OR and NOT operators.
The results showed that there is significant relationship between MSDs and psychological health with road accidents involving drivers of heavy vehicles (p Physical and psychological health can influence the safe operation of heavy vehicle drivers. The fuzzy inference system provided a method that is advantageous and with promising results for modeling of road accident risk levels on the basis of driver’s physical and mental health.

Occupational stress and employee's health status can affect their productiveness and quality of services. Therefore, it is necessary to evaluate the effective factors in this regard. This study was conducted in order to evaluate the relation between psychological health and occupational stress among the midwives employed at the governmental and private hospitals of Neyshabur, Iran.
In this cross-sectional (descriptive and analytical) study, all of the employed midwives in the governmental and private hospitals of Neyshabur (78 people) were enrolled in the study in 2015. Data was gathered through the standard Goldberg General Health Questionnaire and the Altmaier's Occupational Stress Questionnaire was used. Data analysis was done with SPSS 20.
This research showed that only 14% of the midwives were psychologically healthy, and 86% had some degrees of psychological disorders. Also 54%of them were averagely stressed and 46% suffered from severe stress. The results of this research showed an opposite and significant association between psychological health and occupational stress in midwives (p=0.049).
This study showed that most midwives working in these hospitals suffered from psychological disorders. Probably occupational stress was involved in deteriorating their psychological health.

Spreading wood particles and attached colored materials in work places can cause many problems for woodwork industry workers. The aim of this study is to design and implement a local exhaust ventilation system to control wood dust and isocyanates simultaneously.
The study was conducted on 18 workers in the paint workroom of a wood door industry. At first, an overview of the workplace indoor air was done in 18 workstations. The National Institute for Occupational Safety and Health (NIOSH) method was used to measure the concentration of wood dust and TDI(2,4-toluenediisocyanate). In order to control the worker exposure to the pollutants, a semi-downdraft spray chamber was chosen and implemented on the basis of American Conference of Government Industrial Hygienists (ACGIH) control air pollution method. Orifice scrubber was used to avoid entry of pollutants into the environment. Finally, after the establishment of a new ventilation system, the emissions were remeasured and the results were evaluated.
Before design and implementation of local exhaust ventilation system, the emissions in workstations were measured as 0.0015 ± 0.0074 ppm for TDI and 0.01 ± 0.42 mg/m3 for total dust. Then, the pollution concentrations were measured after implementing the local exhaust ventilation system. The concentration of TDI and total dust were measured respectively as 0.007 ± 0.003 ppm and0.07 ± 0.15 which had a significant (p˂0.05) lower concentration than before the implementation. Also, the measured concentrations after the implementation had met the National Institute of Occupational Safety and Health limits: (TLVTWA = 0.005ppm for TDI and TLWTWA = 0.5 mg/m3 for total dust).
The result shows that the current ventilation system (before implementing and spray chamber) was suitable for dusts, but not for the TDI. So, the workers were exposed to non-standard levels of isocyanate. After design and implementation of the spray chamber, the pollutants were clearly decreased (P