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1.
Work ; 68(3): 711-719, 2021.
Article in English | MEDLINE | ID: mdl-33612515

ABSTRACT

BACKGROUND: The study aimed to assess the interactive effects of industrial noise type, level and frequency characteristics on hand motor skills using the Minnesota Manual Dexterity Test and the Hand Tool Dexterity Test. METHODS: A total of ten nonsmoking male volunteers with normal hearing and vision were selected for this study. The study followed a full 3×3×2 factorial design. Independent variables were noise type (steady, intermittent and fluctuating), noise level (75, 85 and 95 dBA) and frequency characteristics ("roar" <2000 Hz and "hiss" >2000 Hz). RESULTS: For Minnesota Manual Dexterity Test, the lowest speed is related to steady hiss noise at 75 dBA and the highest speed is related to fluctuating roar noise at 95 dBA. The speed is being significantly affected by the frequency characteristic (P = 0.041) and noise type (P = 0.025). The effect of hiss noise on speed is greater than roar noise (P = 0.038). There is a significant difference (P = 0.035) between continuous noise and fluctuating noise. For the Hand Tool Dexterity Test, the lowest speed is related to fluctuating hiss noise at 95 dBA and the highest speed is related to steady roar noise at 95 dBA. The speed is being significantly affected by the frequency characteristic (P = 0.002), noise type (P = 0.0001) and noise level (P = 0.005). The effect of hiss noise on response variable to be greater than roar noise (P = 0.008). There is a significant difference (P = 0.0001) between steady noise and the two other types of noise, and also there is a significant difference between 75 dBA and 85 dBA level (P = 0.003). CONCLUSIONS: The results showed that on hand motor skills, speed response was influenced by three characteristics: the type of noise, frequency characteristics and noise level. Also, the effect of the hiss noise was more than the roar noise.


Subject(s)
Hand , Motor Skills , Humans , Industry , Male , Minnesota , Noise/adverse effects
2.
Int J Occup Saf Ergon ; 27(3): 654-663, 2021 Sep.
Article in English | MEDLINE | ID: mdl-31538862

ABSTRACT

Purpose. The probability of being injured or killed from an occupational incident is much higher than a process mishap in the oil and gas industry. The aim of this study was to establish a model for predicting the probability of occupational fall incidents using Bayesian networks. Methods. The study was performed in a selected number of oil refineries. Bayesian network variables (n = 18) were identified using literature as well as expert knowledge. These contributing factors were categorized into four layers (organizational, supervisory, preconditions and unsafe acts) according to the Swiss cheese model. Causal relationships among contributing factors were determined using expert judgment in combination with Dempster-Shafer theory. The conditional probability table of each contributing factor was measured using a questionnaire. Results. The prior probability of fall events was 5.34% (53 cases per 1000 operational workers in 12 months). The posterior probability predicted that using fall protection devices and safe working platforms will decrease more than half (58%) of fall occupational incidents. Conclusion. Bayesian network features including graphical representation, easy belief updating, performance testing and sensitivity analysis facilitate the process of predicting occupational incident probability including fall events. The proposed approach is a step toward quantitative risk analysis of occupational incidents.


Subject(s)
Industry , Bayes Theorem , Humans , Probability , Risk Assessment , Surveys and Questionnaires
3.
J Environ Health Sci Eng ; 18(2): 441-450, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33312573

ABSTRACT

BACKGROUND: This ecological study aims to model the trend of changes in exposure of outdoor workers to heat stress in outdoors in the coming decades with the use of the Wet-Bulb Globe Temperature (WBGT), Hadley Coupled Atmosphere- Ocean General Circulation Model, version 3 (HADCM3), and Long Ashton Research Station Weather Generator (LARS-WG) in Tehran, Iran, considering the climate change and the global warming. METHODS: The hourly values of environmental parameters including minimum and maximum air temperature, relative humidity, precipitation and radiation related to Prakash , Shahriar and Damavand cities were obtained from the Meteorological Organization of Iran. These data were recorded during 1965 to 2015. The climate modeling was done for 2011-2030, 2046-2065, and 2080-2099. RESULTS: The minimum and maximum air temperatures in the different months of the year in the three studied cities show an increasing trend. Our finding shows that the WBGT will be increased by 2099. In Pakdasht, this index will be close to the danger zone in the coming years, especially in 2080-2099. CONCLUSIONS: All the results obtained indicate an increase in risk of heat stress in outdoor workplaces, given the global warming.

4.
J Environ Health Sci Eng ; 17(1): 151-159, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31321043

ABSTRACT

PURPOSE: Over the past decades, mobile phone usage have increased dramatically. Extensive development and use of mobile telecommunication services has increased exposure to radio frequency electromagnetic waves (RF-EMW) in the daily lives of humans, and concerns about the harmful effects of mobile phones have also increased on human health. Therefore, this study aimed to investigate the effect of battery charge levels of the mobile phone on electromagnetic waves emission. METHODS: The mobile phone used in the current study was HTC One E9+ (0.181 W/kg SAR) with a non-removable battery model Li-Po 2800 mAh. The power density was measured with the mobile phone set to operate at the 2G mode by a SMP2 Portable Electromagnetic Field Monitoring System. Power density was measured in Calling mode (50 sec), Called mode (40 sec) and Talking mode (360 sec) at the battery charge levels of 1, 5, 10, 15, 20, 30, 50, 60, 70, 80 and 100%. RESULTS: In Calling mode, the maximum electromagnetic waves were determined when the mobile phone had 1% battery charge and also while it was being charged. Contrary to Calling mode, there is no statistically significant difference between the power density emitted in Called mode and Talking mode at the various battery charge levels. Power density was found to be highest in the Called mode (29.11 µw/cm2), and to be higher in the Talking mode (23.005 µw/cm2) than in the Calling mode (10.27 µw/cm2). CONCLUSIONS: The data of the present study can be used to monitor the daily exposure of mobile phone users as well as to estimate exposure levels in the laboratory and non-laboratory studies. As long as a mobile phone that is in the standby mode remains within the geographic domain of the operator's service zone, the power density emitted from that phone will be virtually zero, and any background wave can be attributed to other sources.

5.
Environ Monit Assess ; 190(2): 97, 2018 Jan 25.
Article in English | MEDLINE | ID: mdl-29372415

ABSTRACT

Accidents are among the main problems in the oil product supply chain. The most important effective factors in these events are the kind of trucks used and their health, safety, and environment (HSE) condition. The aim of this study was to present a conceptual pattern of the HSE performance of oil trucks in oil industries. In this study, 20 truck models (with fixed tanks), in use over different periods of time, were investigated. In this regard, the criteria and sub-criteria were first determined in two parts-carrier and tank-and weighted by fuzzy analytical hierarchy process (FAHP). The results showed that the most important sub-criteria regarding the HSE factors of the carrier were resistance and strength of the front and rear shields, the brake system, and the ventilation system. The most important sub-criteria regarding the HSE factors of the tank were tank shell thickness and a good tank design shape with respect to portable material. It should be noted that the weight of the criteria with each other and sub-criteria with each other are not equal. This issue is important for decision-making. The main reason for the use of trucks with the lowest score in developing countries is the lack of attention by managers to safety issues and international standards and agreements such as the ADR.


Subject(s)
Environmental Health , Environmental Monitoring , Motor Vehicles , Decision Making , Environment , Humans , Protective Devices , Safety
6.
Noise Health ; 19(89): 200-206, 2017.
Article in English | MEDLINE | ID: mdl-28816207

ABSTRACT

INTRODUCTION: Noise exposure may have anatomical, nonauditory, and auditory influences. Considering nonauditory impacts, noise exposure can cause alterations in the automatic nervous system, including increased pulse rates, heightened blood pressure, and abnormal secretion of hormones. The present study aimed at examining the effect of various sound pressure levels (SPLs) on the serum aldosterone level among rats. MATERIALS AND METHODS: A total of 45 adult male rats with an age range of 3 to 4 months and a weight of 200 ± 50 g were randomly divided into 15 groups of three. Three groups were considered as the control groups and the rest (i.e., 12 groups) as the case groups. Rats of the case groups were exposed to SPLs of 85, 95, and 105 dBA. White noise was used as the noise to which the rats were exposed. To measure the level of rats' serum aldosterone, 3 mL of each rat's sample blood was directly taken from the heart of anesthetized animals by using syringes. The taken blood samples were put in labeled test tubes that contained anticoagulant Ethylenediaminetetraacetic acid. In the laboratory, the level of aldosterone was assessed through Enzyme-linked immunosorbent assay protocol. The collected data were analyzed by the use of Statistical Package for Social Sciences (SPSS) version 18. RESULTS: The results revealed that there was no significant change in the level of rats' serum aldosterone as a result of exposure to SPLs of 65, 85, and 95 dBA. However, the level of serum aldosterone experienced a remarkable increase after exposure to the SPL of 105 dBA (P < 0.001). Thus, the SPL had a significant impact on the serum aldosterone level (P < 0.001). In contrast, the exposure time and the level of potassium in the used water did not have any measurable influence on the level of serum aldosterone (P = 0.25 and 0.39). CONCLUSION: The findings of this study demonstrated that serum aldosterone can be used as a biomarker in the face of sound exposure.


Subject(s)
Aldosterone/blood , Environmental Exposure/adverse effects , Sound/adverse effects , Acoustic Stimulation/methods , Animals , Male , Noise/adverse effects , Pressure , Rats
7.
Ind Health ; 55(5): 437-443, 2017 Oct 07.
Article in English | MEDLINE | ID: mdl-28804096

ABSTRACT

The purpose of this article is to examine the applicability of Universal Thermal Climate Index (UTCI) index as an innovative index for evaluating of occupational heat stress in outdoor environments. 175 workers of 12 open-pit mines in Tehran, Iran were selected for this research study. First, the environmental variables such as air temperature, wet-bulb temperature, globe temperature, relative humidity and air flow rate were measured; then UTCI, wet-bulb globe temperature (WBGT) and heat stress index (HSI) indices were calculated. Simultaneously, physiological parameters including heart rate, oral temperature, tympanic temperature and skin temperature of workers were measured. UTCI and WBGT are positively significantly correlated with all environmental parameters (p<0.03), except for air velocity (r<-0.39; p>0.05). Moreover, a strong significant relationship was found between UTCI and WBGT (r=0.95; p<0.001). The significant positive correlations exist between physiological parameters including oral temperature, tympanic and skin temperatures and heart rate and both the UTCI and WBGT indices (p<0.029). The highest correlation coefficient has been found between the UTCI and physiological parameters. Due to the low humidity and air velocity (~<1 m/s) in understudied mines, UTCI index appears to be appropriate to assess the occupational heat stress in these outdoor workplaces.


Subject(s)
Heat Stress Disorders/prevention & control , Miners , Occupational Diseases/prevention & control , Occupational Exposure/adverse effects , Adult , Air Movements , Body Temperature , Climate , Cross-Sectional Studies , Heart Rate , Humans , Humidity , Iran , Male , Middle Aged , Skin Temperature
8.
Saf Health Work ; 8(2): 151-155, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28593070

ABSTRACT

BACKGROUND: At the entrance of a tunnel, reflection of sunlight from the surrounding environment and a lack of adequate lighting usually cause some vision problems. The purpose of this study was to perform a safety evaluation of lighting on a very long road in Ilam, Iran. METHODS: The average luminance was measured using a luminance meter (model S3; Hagner, Solna, Sweden). A camera (model 108, 35-mm single-lens reflex; Yashica, Nagano, Japan) was used to take photographs of the safe stopping distance from the tunnel entrance. Equivalent luminance was determined according to the Holliday polar diagram. RESULTS: Considering the average luminance at the tunnel entrance (116.7 cd/m2) and using Adrian's equation, the safe level of lighting at the entrance of the tunnel was determined to be 0.7. CONCLUSION: A comparison between the results of the safe levels of lighting at the entrance of the tunnel and the De Boer scale showed that the phenomenon of black holes is created at the tunnel entrance. This may lead to a misadaptation of the drivers' eyes to the change in luminance level at the entrance of the tunnel, thereby increasing the risk of road accidents in this zone.

9.
Article in English | MEDLINE | ID: mdl-28101366

ABSTRACT

BACKGROUND: Heat stress as a physical harmful agent can increase the risk of health and safety problems in different workplaces such as mining. Although there are different indices to assess the heat stress imposed on workers, choosing the best index for a specific workplace is so important. Since various criteria affect an index applicability, extracting the most effective ones and determining their weights help to prioritize the existing indices and select the optimal index. METHODS: In order to achieve this aim, present study compared some heat stress indices using effective methods. The viewpoints of occupational health experts and the qualitative Delphi methods were used to extract the most important criteria. Then, the weights of 11 selected criteria were determined by Fuzzy Analytic Hierarchy Process. Finally, fuzzy TOPSIS technique was applied for choosing the most suitable heat stress index. RESULTS: According to result, simplicity, reliability, being low cost, and comprehensiveness were the most determinative criteria for a heat stress index. Based on these criteria and their weights, the existing indices were prioritized. Eventually, wet bulb glob temperature appropriated the first priority and it was proposed as an applicable index for evaluating the heat stress at outdoor hot environments such as surface mines. CONCLUSIONS: The use of these strong methods allows introducing the most simple, precise, and applicable tool for evaluation the heat stress in hot environments. It seems that WBGT acts as an appropriate index for assessing the heat stress in mining activities at outdoors.

10.
Noise Health ; 18(85): 391-398, 2016.
Article in English | MEDLINE | ID: mdl-27991472

ABSTRACT

INTRODUCTION: Noise is considered as the most common cause of harmful physical effects in the workplace. A sound that is generated from within the inner ear is known as an otoacoustic emission (OAE). Distortion-product otoacoustic emissions (DPOAEs) assess evoked emission and hearing capacity. The aim of this study was to assess the signal-to-noise ratio in different frequencies and at different times of the shift work in workers exposed to various levels of noise. It was also aimed to provide a statistical model for signal-to-noise ratio (SNR) of OAEs in different frequencies based on the two variables of sound pressure level (SPL) and exposure time. MATERIALS AND METHODS: This case-control study was conducted on 45 workers during autumn 2014. The workers were divided into three groups based on the level of noise exposure. The SNR was measured in frequencies of 1000, 2000, 3000, 4000, and 6000 Hz in both ears, and in three different time intervals during the shift work. According to the inclusion criterion, SNR of 6 dB or greater was included in the study. The analysis was performed using repeated measurements of analysis of variance, spearman correlation coefficient, and paired samples t-test. RESULTS: The results showed that there was no statistically significant difference between the three exposed groups in terms of the mean values of SNR (P > 0.05). Only in signal pressure levels of 88 dBA with an interval time of 10:30-11:00 AM, there was a statistically significant difference between the right and left ears with the mean SNR values of 3000 frequency (P = 0.038). The SPL had a significant effect on the SNR in both the right and left ears (P = 0.023, P = 0.041). The effect of the duration of measurement on the SNR was statistically significant in both the right and left ears (P = 0.027, P < 0.001). CONCLUSION: The findings of this study demonstrated that after noise exposure during the shift, SNR of OAEs reduced from the beginning to the end of the shift.


Subject(s)
Hearing Loss, Noise-Induced/physiopathology , Noise, Occupational , Occupational Diseases/physiopathology , Occupational Exposure , Otoacoustic Emissions, Spontaneous , Signal-To-Noise Ratio , Adult , Case-Control Studies , Humans , Iran , Male , Time Factors
11.
Noise Health ; 18(80): 1-6, 2016.
Article in English | MEDLINE | ID: mdl-26780955

ABSTRACT

The existing literature indicates that occupational exposure to noise may have adverse effects on workers' health. The aim of this study was to evaluate the possible effects of exposure to different sound pressure levels (SPLs) on serum aldosterone and potassium concentration among Iranian blue collar workers in Golgohar Mining and Industrial Company in Sirjan, Kerman Province, Iran. This case-control study was performed on 45 workers of Golgohar Mining and Industrial Company. The subjects consisted of 30 workers from manufacturing departments and 15 office employees of the mining company. The controls, mainly with administrative jobs were exposed to 72 dBA SPL. Cases, in two separate groups, were exposed to noise levels of 88 dBA and 103 dBA, respectively. Noise intensity was measured at the desired locations. Noise measurements were performed according to the International Organization for Standardization (ISO) 9612. To measure the serum aldosterone and potassium concentrations, a 5 mL blood sample was taken from each worker at the specified time intervals and aldosterone concentration was determined using enzyme-linked immunosorbent assay (ELISA) test in the laboratory. Repeated measurement and Spearman's correlation coefficient analysis were used with α = 0.05. Exposure to the different levels of sound pressure resulted in different aldosterone concentrations and meanwhile an increase in the SPL did not affect the concentration of potassium. From 10:00 AM to 10:30 AM, as SPL increased, aldosterone concentrations did not increase significantly but from 13:30 PM to 14:00 PM, raised SPL led to a significant increase in aldosterone concentration. However, there was no correlation between the concentration of potassium and different factors. This study indicated that increases in SPLs affect aldosterone concentration but at the same time do not have significant effects on serum potassium level.


Subject(s)
Aldosterone/blood , Mining , Noise, Occupational/adverse effects , Potassium/blood , Adult , Biomarkers/blood , Case-Control Studies , Cross-Sectional Studies , Hearing Loss, Noise-Induced/etiology , Humans , Iran
12.
Arch Environ Occup Health ; 71(3): 178-85, 2016 May 03.
Article in English | MEDLINE | ID: mdl-26418847

ABSTRACT

Systematic and cooperative interactions among parent industry and contractors are necessary for a successful health, safety, and environmental management system (HSE-MS). This study was conducted to evaluate the HSE-MS performance in contracting companies in one of the petrochemical industries in Iran during 2013. Managers of parent and contracting companies participated in this study. The data collection forms included 7 elements of an integrated HSE-MS (leadership and commitment; policy and strategic objectives; organization, resources, and documentation; evaluation and risk management; planning; implementation and monitoring; auditing and reviewing). The results showed that mean percentage of the total scores in seven elements of HSE-MS was 85.7% and 87.0% based on self-report and report of parent company, respectively. In conclusion, this study showed that HSE-MS was desirably functioning; however, improvement to ensure health and safety of workers is still required.


Subject(s)
Contracts , Cooperative Behavior , Occupational Health/standards , Administrative Personnel/psychology , Cross-Sectional Studies , Humans , Interviews as Topic , Iran , Oil and Gas Industry , Organizational Case Studies , Qualitative Research , Risk Management
13.
Electron Physician ; 7(3): 1126-34, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26388979

ABSTRACT

BACKGROUND: Noise-induced hearing loss (NIHL) is usually one of the main problems in industrial settings. The aim of this study was to determine whether changes in the signal-to-noise ratio (SNR) in different DPOAE are caused by exposure to different levels of noise at different time intervals among workers exposed to noise. METHODS: This case-control study was conducted in the autumn of 2014 on 45 workers at Gol Gohar Mining and Industrial Company, which is located in Sirjan in southeast Iran. The workers were divided into three groups based on their noise exposure, i.e., 1) 15 office workers as a control group with exposure to low levels of noise, 2) 15 workers from manufacturing departments who were exposed to a medium level of noise, and 3) 15 workers from manufacturing departments who were exposed to high levels of noise. The SNRs at the frequencies of 1000, 2000, 3000, 4000, and 6000 Hz were measured in both ears at three different time intervals during the shift work. SNRs of 6 or greater were considered as inclusion criterion. Repeated measures, the Spearman rank-order correlation test, and paired t-test analyses were used with α = 0.05 being the level of significance. RESULTS: For all frequencies in the right and left ears, the SNR values were more than 6, thus all SNR values were considered as acceptable responses. The effects of time and sound pressure level (SPL) on SNR were significant for the right and left ears (p = 0.027 and < 0.001, respectively). There was a statistically significant correlation between the SNR values in the right and left ears for the time intervals 7:30-8:00 A.M. and 13:30-14:00 P.M., which implied that an increase in the duration of exposure led to reduced SNR values (p = 0.024, r = 0.948). CONCLUSIONS: The comparison of the SNR values in the right and left ears (for all frequencies and the three different SPLs) indicated that the values decreased during the shift work.

14.
Glob J Health Sci ; 8(1): 180-8, 2015 May 17.
Article in English | MEDLINE | ID: mdl-26234977

ABSTRACT

INTRODUCTION: Hearing protection devices are one of the primary noise reduction tools in developing countries. This study is intended to produce and apply acrylonitrile butadiene styrene (ABS)/clay nanocomposites to fabricate a laboratory single cup earmuffs and then compare it with double cup and single cup pure ABS earmuffs in terms of noise attenuation performance and comfort. In addition, the noise attenuation performance of single cup pure ABS earmuffs is compared with double cup pure ABS earmuffs. METHODS: ABS/nanoclay filament was fabricated using a twin screw extruder. A three dimensional (3D) printing machine and a 3D model of earcup, designed by solid work software, were applied to print single and double cup earmuffs using ABS/nanoclay composite and pure ABS filaments. Finally, using an acoustic test fixture, objective noise attenuation test was performed on three different types of earmuffs, including with and without nano material and a secondary cup. Moreover, earmuffs weight was measured as a comfort component. RESULTS: Insertion loss and calculated noise reduction rating (NRR) of single cup ABS/nanoclay earmuffs (NRR=19.4 dB) and double cup pure ABS earmuffs (NRR=18.93 dB) were improved in comparison with single cup pure ABS earmuffs (NRR=15.7 dB). Additionally, both single cup earmuffs were significantly lighter than double cup earmuffs. Although single cup nano and double cup earmuffs had nearly the same attenuation performance, single cup nano earmuffs were 74 gr lighter than double cup earmuffs, so with reference to comfort, single cup nano earmuffs will probably be more acceptable. CONCLUSIONS: From this survey it might be concluded that, even though single cup ABS/nanoclay earmuffs was lighter than double cup pure ABS earmuffs, it had approximately more attenuation performance in comparison with double cup pure ABS earmuffs. Consequently, users are probably more prone to wear light- weight single cup ABS/nanoclay earmuffs as a result of improved comfort. In short, ABS/nanoclay composite can be considered a good choice in products with the necessity of high acoustic performance and low weight.


Subject(s)
Acoustics , Ear Protective Devices/standards , Hearing Loss, Noise-Induced/prevention & control , Nanocomposites/chemistry , Noise/adverse effects , Printing, Three-Dimensional , Equipment Design , Humans , Loudness Perception , Risk Assessment
15.
Int J Occup Med Environ Health ; 28(3): 625-34, 2015.
Article in English | MEDLINE | ID: mdl-26190737

ABSTRACT

OBJECTIVES: Spatial assessment of traffic noise pollution intensity will provide urban planners with approximate estimation of citizens exposure to impermissible sound levels. They could identify critical noise pollution areas wherein noise barriers should be embedded. The present study aims at using the Geographic Information System (GIS) to assess spatial changes in traffic noise pollution in Tehran, the capital of Iran, and the largest city in the Middle East. MATERIAL AND METHODS: For this purpose, while measuring equivalent sound levels at different time periods of a day and different days of a week in District 14 of Tehran, wherein there are highways and busy streets, the geographic coordination of the measurement points was recorded at the stations. The obtained results indicated that the equivalent sound level did not show a statistically significant difference between weekdays, and morning, afternoon and evening hours as well as time intervals of 10 min, 15 min and 30 min. Then, 91 stations were selected in the target area and equivalent sound level was measured for each station on 3 occasions of the morning (7:00-9:00 a.m.), afternoon (12.00-3:00 p.m.) and evening (5:00-8:00 p.m.) on Saturdays to Wednesdays. RESULTS: As the results suggest, the maximum equivalent sound level (Leq) was reported from Basij Highway, which is a very important connecting thoroughfare in the district, and was equal to 84.2 dB(A), while the minimum equivalent sound level (Leq), measured in the Fajr Hospital, was equal to 59.9 dB(A). CONCLUSIONS: The average equivalent sound level was higher than the national standard limit at all stations. The use of sound walls in Highways Basij and Mahallati as well as widening the Streets 17th Shahrivar, Pirouzi and Khavaran, benchmarked on a map, were recommended as the most effective mitigation measures. Additionally, the research findings confirm the outstanding applicability of the Geographic Information System in handling noise pollution data towards depicting noise pollution intensity caused by traffic.


Subject(s)
Cities , Environmental Illness/epidemiology , Noise, Transportation/adverse effects , Risk Assessment/methods , Environmental Illness/diagnosis , Humans , Incidence , Iran/epidemiology , Pilot Projects , Time Factors
16.
J Occup Health ; 55(3): 204-10, 2013.
Article in English | MEDLINE | ID: mdl-23485573

ABSTRACT

OBJECTIVES: Noise is probably the most common occupational hazard facing workers today. This paper presents a model to evaluate and select a unit as the first priority for implementing noise control measures from the different parts of an industrial complex. METHODS: For this purpose, a formula was proposed as a priority risk index (NCPI) by considering some criteria, including: the number of exposed workers in each part, their exposure times and the range of sound pressure level. The above criteria were weighed by appending weighting factors, which can be different based upon the environmental noise levels. The environmental noise measurements were also carried out by lattice method according to ISO 9612:2009. At the next stage, the numbers of stations that fell within the desired ranges in the weighting factors table were found. then the priorities were identified using the above criteria and the NCPI. RESULTS: The results indicate that the compression unit of air plant had the highest score among the different departments of the company under study (NCPI=0.3). Using this model is easy and fast. It is applicable to similar industries and also offers valuable information for prioritizing noise control measures. CONCLUSIONS: Therefore, it will be possible to minimize worker exposure to noise in the most polluted places in any industry by identifying the main noise sources and implementing measures suitable for controlling the risk.


Subject(s)
Hearing Loss, Noise-Induced/prevention & control , Noise, Occupational/prevention & control , Occupational Diseases/prevention & control , Occupational Exposure/prevention & control , Petroleum , Risk Management/methods , Humans , Occupational Exposure/statistics & numerical data , Occupational Health
17.
Health Phys ; 104(1): 87-94, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23192091

ABSTRACT

Extremely Low-Frequency (ELF) electric and magnetic fields belonging to the nonionizing electromagnetic radiation spectrum have a frequency of 50 - 60 Hz. All people are exposed to a complex set of electric and magnetic fields that spread throughout the environment. The current study was carried out to assess people's exposure to an ELF electric field in the Tehran metropolitan area in 2010. The measurement of the electronic fields was performed using an HI-3604 power frequency field strength measurement device. A total number of 2,753 measurements were performed. Afterward, the data obtained were transferred to the base map using Arc View Version 3.2 and Arc Map Version 9.3. Finally, an interpolation method was applied to expand the intensity of the electric field to the entire city. Based on the results obtained, the electric field was divided into three parts with various intensities including 0-5 V m, 5-15 V m, and >15 V m. It should be noted that the status of high voltage transmission lines, electric substations, and specific points including schools and hospitals were also marked on the map. Minimum and maximum electric field intensities were measured tantamount to 0.31 V m and 19.80 V m, respectively. In all measurements, the electric field was much less than the amount provided in the ICNIRP Guide. The results revealed that 141 hospitals and 6,905 schools are situated in an area with electric field intensity equal to 0-5 V m, while 15 hospitals and 95 schools are located in zones of 5-15 V m and more than 15 V m. Examining high voltage transmission lines and electric substations in Tehran and its suburbs suggested that the impact of the lines on the background electric field of the city was low. Accordingly, 0.97 km of Tehran located on the city border adjacent to the high voltage transmission lines have an electric field in the range of 5 to 15 V m. The noted range is much lower than the available standards. In summary, it can be concluded that the public is not exposed to a risky background electric field in metropolitan Tehran. The result of comparing sensitive recipients showed that the schools have a more desirable status than the hospitals. Nonetheless, epidemiologic studies can lead to more understanding of the impact on public health.


Subject(s)
Electromagnetic Fields , Environmental Monitoring/methods , Environmental Exposure , Humans , Iran , Time Factors
18.
Noise Health ; 14(59): 135-9, 2012.
Article in English | MEDLINE | ID: mdl-22918142

ABSTRACT

Noise may be defined as any unwanted sound. Sound becomes noise when it is too loud, unexpected, uncontrolled, happens at the wrong time, contains unwanted pure tones or unpleasant. In addition to being annoying, loud noise can cause hearing loss, and, depending on other factors, can affect stress level, sleep patterns and heart rate. The primary object for determining subjective estimations of loudness is to present sounds to a sample of listeners under controlled conditions. In heating, ventilation and air conditioning (HVAC) systems only the ventilation fan industry (e.g., bathroom exhaust and sidewall propeller fans) uses loudness ratings. In order to find satisfaction, percent of exposure to noise is the valuable issue for the personnel who are working in these areas. The room criterion (RC) method has been defined by ANSI standard S12.2, which is based on measured levels of in HVAC systems noise in spaces and is used primarily as a diagnostic tool. The RC method consists of a family of criteria curves and a rating procedure. RC measures background noise in the building over the frequency range of 16-4000 Hz. This rating system requires determination of the mid-frequency average level and determining the perceived balance between high-frequency (HF) sound and low-frequency (LF) sound. The arithmetic average of the sound levels in the 500, 1000 and 2000 Hz octave bands is 44.6 dB; therefore, the RC 45 curve is selected as the reference for spectrum quality evaluation. The spectral deviation factors in the LF, medium-frequency sound and HF regions are 2.9, 7.5 and -2.3, respectively, giving a Quality Assessment Index (QAI) of 9.8. This concludes the QAI is useful in estimating an occupant's probable reaction when the system design does not produce optimum sound quality. Thus, a QAI between 5 and 10 dB represents a marginal situation in which acceptance by an occupant is questionable. However, when sound pressure levels in the 16 or 31.5 Hz octave bands exceed 65 dB, vibration in lightweight office construction is possible.


Subject(s)
Air Conditioning , Heating , Noise, Occupational , Occupational Exposure/adverse effects , Ventilation , Acoustic Stimulation , Humans , Job Satisfaction , Loudness Perception , Occupational Exposure/standards
19.
Noise Health ; 14(59): 184-9, 2012.
Article in English | MEDLINE | ID: mdl-22918149

ABSTRACT

Measuring non-auditory effects of noise such as stress-inducing ones have become of interest recently. Salivary cortisol has become a popular measure in stress research. So, assessing noise-induced stress via saliva cortisol evaluation can present a bright future in non-invasive exposure assessment methods. This study had 3 goals: (1) Assess and compare saliva cortisol concentrations in the morning and evening in normal work day and leisure day in industrial workers, (2) assess the relationship between industrial noise exposure and salivary cortisol concentrations, and (3) assess the possibility of using salivary cortisol as a possible marker of noise-induced stress. This study included 80 male participants working in 4 different parts (painting, assembling lines, casting, and packaging) of a household manufacturing company. Morning and evening saliva samples were collected at 7.00 am and 4.00 pm, respectively. Noise exposure levels were assessed by sound level meter and noise dosimeter. All measurements occurred in two days: One in leisure day and other in working day. Descriptive statistics, paired sample t-test, and regression analysis were used as statistical tools of this study with P < 0.05. On the leisure day, morning salivary cortisol (geometric mean [GM], 15.0; 95% CI, 12.0 to 19.0 nmol/L) was significantly higher than evening cortisol (GM, 5.2; 95% CI, 4.2 to 6.3 nmol/L) (P < 0.05). Also, on the working day, morning salivary cortisol (GM, 14.0; 95% CI, 11.25 to 18.0 nmol/L) was significantly higher than evening cortisol (GM, 8.0; 95% CI, 6.5 to 10.0 nmol/L) (P < 0.05). No significant difference was obtained for morning cortisol levels between leisure day and working day samples (P = 0.117). But, for evening cortisol concentrations, a strong significant difference was noted leisure day and working day (P < 0.001). The evening cortisol in the working day correlated significantly with noise exposure > 80 dBA. Our study revealed that industrial noise, with levels > 80 dBA, has a significant effect on salivary cortisol elevation.


Subject(s)
Hydrocortisone/analysis , Noise, Occupational/adverse effects , Occupational Exposure/adverse effects , Saliva/chemistry , Stress, Psychological/diagnosis , Stress, Psychological/etiology , Adult , Biomarkers/analysis , Circadian Rhythm , Humans , Industry , Leisure Activities , Linear Models , Male , Middle Aged , Regression Analysis
20.
Environ Monit Assess ; 184(5): 2981-91, 2012 May.
Article in English | MEDLINE | ID: mdl-21739281

ABSTRACT

Strategic health, safety, and environmental management system (HSE-MS) involves systematic and cooperative planning in each phase of the lifecycle of a project to ensure that interaction among the industry group, client, contractor, stakeholder, and host community exists with the highest level of health, safety, and environmental standard performances. Therefore, it seems necessary to assess the HSE-MS performance of contractor(s) by a comparative strategic management model with the aim of continuous improvement. The present Strategic Management Model (SMM) has been illustrated by a case study and the results show that the model is a suitable management tool for decision making in a contract environment, especially in oil and gas fields and based on accepted international standards within the framework of management deming cycle. To develop this model, a data bank has been created, which includes the statistical data calculated by converting the HSE performance qualitative data into quantitative values. Based on this fact, the structure of the model has been formed by defining HSE performance indicators according to the HSE-MS model. Therefore, 178 indicators have been selected which have been grouped into four attributes. Model output provides quantitative measures of HSE-MS performance as a percentage of an ideal level with maximum possible score for each attribute. Defining the strengths and weaknesses of the contractor(s) is another capability of this model. On the other hand, this model provides a ranking that could be used as the basis for decision making at the contractors' pre-qualification phase or during the execution of the project.


Subject(s)
Environmental Monitoring , Models, Theoretical , Safety Management/methods , Decision Support Techniques , Environment , Environmental Pollution/statistics & numerical data , Health Surveys , Humans , Oil and Gas Fields
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