[Determining service life of respirator cartridge using a simple and practical method: case study in a car manufacturing industry]

For ensuring about proper performance of air-purifying respirators in providing protection against workplace contaminates, it is necessary to change the respirator cartridges before the end of their service life. The aim of this study was determination of service life of organic vapor cartridges using a simple and practical method in a spray painting booth of a car manufacturing industry. NIOSH Multi Vapor software was used for estimating service life of respirator cartridges based on workplace conditions and cartridge specifications. Efficiency of determined service life was investigated using an apparatus for field testing of cartridges in the workplace. The result showed that existing schedule for changing the respirator cartridges is not effective and no longer provide adequate protection for sprayers against organic contaminants while working in a painting booth. It is necessary to change the cartridges before their estimated service life [every 4 hours]. NIOSH Multi Vapor has acceptable efficiency for determining respirator cartridges service life and could be used as a simple and practical method in the workplace. This software could be used as a simple and practical method in the workplace. Moreover, Service life estimated by this software was confirmed by cartridge field test apparatus

effect of service quality on patient loyalty: a study of private hospitals in Tehran, Iran

Service quality is perceived as an important factor for developing patient's loyalty. The aim of this study was to determine the hospital service quality from the patients' viewpoints and the relative importance of quality dimensions in predicting the patient's loyalty. A cross-sectional study was conducted in 2010.The study sample was composed of 943 patients selected from eight private general hospitals in Tehran. The survey instrument was a questionnaire included 24 items about the service quality and 3 items about the patient's loyalty. Exploratory factor analysis was employed to extracting the dimensions of service quality. Also, regression analysis was performed to determining the relative importance of the service quality dimensions in predicting the patient's loyalty. The mean score of service quality and patient's loyalty was 3.99 and 4.16 out of 5, respectively. About 29% of the loyalty variance was explained by the service quality dimensions. Four quality dimensions [Costing, Process Quality, Interaction Quality and Environment Quality] were found to be key determinants of the patient's loyalty in the private hospitals of Tehran. The patients' experience in relation to the private hospitals' services has strong impact on the outcome variables like willingness to return to the same hospital and reuse its services or recommend them to others. The relationship between the service quality and patient's loyalty proves the strategic importance of improving the service quality for dragging and retaining patients and expanding the market share

study on risk factors of wsd outbreak in choubdeh - abadadan shrimp farming site in 2010

White spot, as one of the infectious viral diseases, has made severe losses in shrimp ponds all over the world. Despite extensive efforts made to deal with and control the disease, white spot continues to be a major health problem in shrimp farms across Iran. In this work, the significance of the risk factors of white spot disease epidemic occurred in shrimp ponds of Choubdeh farming site in Khuzestan province of Iran is determined. A cross sectional study was conducted from June 1, 2010, to September 22, 2010 in 223 shrimp ponds of the site. Data was collected on 17 variables, thought to be associated with the occurrence and epidemic of white spot, with the aid of the shrimp ponds owners and fisheries and veterinary organizations. The occurrence of white spot disease in the farming site was determined by clinical symptoms and the results of conventional PCR tests, the effectiveness of the risk factors was established by odds ratio [OR]. It is found that poor management of birds fighting [OR=3.72], less educated farm foreman [OR=3.29] and poor filtration of the intake water [OR= 3.43] are significantly affected the occurrence of the disease while little changes in the salinity of shrimp ponds [OR =0.1 6] decreases the odds of the disease. These findings help better develop shrimp farming across Iran, especially in Khuzestan province

[Evaluation of change schedule of organic vapor respirator cartridges in a petrochemical industry]

In the absence of End of Service Life Indicator [ESLI], a cartridge change schedule should be established for ensuring that cartridges are changed before their end of service life. The aim of this study was determining the efficiency of respirator change schedule and presenting a suitable schedule for changing the cartridges before their end of service life in a petrochemical complex. Required information for change criteria, number and time between changing the cartridges were gathered through the existing records in the industry. Also the highest values of measured environmental conditions were used as a worse case condition for estimation of service life of cartridges. Technical data and specification of used cartridges in the industry were collected through the cartridges manufactures. Manufacturer's service life software was used for estimation of cartridge service life and 10% of threshold limit values were considered for estimation of breakthrough time of cartridges. The results show that there is no effective change schedule for respirator cartridges in the studied industry. Also there was a significant difference between current schedule and developed schedule for changing the respirators in the studied industry. Relying on odor thresholds and other warning properties solely as the basis for changing respirator chemical cartridges is not allowed and a change out schedule should be developed base on workplace conditions and specification of respirator cartridges

Presence of atrazine in the biological samples of cattle and its consequence adversity in human health

Cattle can be considered as an important source for herbicides through nutrition. Therefore, herbicide residue in animal products is a potential human exposure to herbicides causing public health problems in human life. Triazines are a group of herbicides primarily used to control broadleaf weeds in corn and other feed ingredients and are considered as possible human carcinogens. To evaluate trace residue of these pollutants molecular imprinted solid phase extraction [MISPE] method has been developed, using biological samples. Blood samples were taken from the jugular vein of 45 Holstein cows in 3 commercial dairy farms in Khuzestan Province, Iran. Urine samples were also taken from the cows. The mean +/- SD concentrations of atrazine in serum and urine samples of the study group [0.739 +/- 0.567 ppm and 1.389 +/- 0.633 ppm, respectively] were higher [P < 0.05] than the concentrations in serum and urine samples of the control group [0.002 +/- 0.005 ppm and 0.012 +/- 0.026 ppm, respectively]. Atrazine in the feed ingredients ingested by cattle could be transferred into the biological samples and consequently can be considered as a potential hazard for the public health

Molecularly imprinted solid phase extraction for trace analysis of diazinon in drinking water

Amongst organophosphate pesticides, the one most widely used and common environmental contaminant is diazinon; thus methods for its trace analysis in environmental samples must be developed. Use of diazinon imprinted polymers such as sorbents in solid phase extraction, is a prominent and novel application area of molecular imprinted polymers. For diazinon extraction, high performance liquid chromatography analysis was demonstrated in this study. During optimization of the molecular imprinted solid phase extraction procedure for efficient solid phase extraction of diazinon, Plackett-Burman design was conducted. Eight experimental factors with critical influence on molecular imprinted solid phase extraction performance were selected, and 12 different experimental runs based on Plackett-Burman design were carried out. The applicability of diazinon imprinted polymers as the sorbent in solid phase extraction, presented obtained good recoveries of diazinon from LC-grade water. An increase in pH caused an increase in the recovery on molecular imprinted solid phase extraction. From these results, the optimal molecular imprinted solid phase extraction procedure was as follows: solid phase extraction packing with 100 mg diazinon imprinted polymers; conditioning with 5 mL of methanol and 6 mL of LC-grade water; sample loading containing diazinon [pH=10]; washing with 1 mL of LC-grade water, 1 mL LC- grade water containing 30% acetonitrile and 0.5 mL of acetonitrile, respectively; eluting with 1 mL of methanol containing 2% acetic acid. The percentage recoveries obtained by the optimized molecular imprinted solid phase extraction were more than 90% with drinking water spiked at different trace levels of diazinon. Generally speaking, the molecular imprinted solid phase extraction procedure and subsequent high performance liquid chromatography analysis can be a relatively fast and proper approach for qualitative and quantitative analysis of diazinon in drinking water

Molecular imprinted solid phase extraction for determination of atrazine in environmental samples

Solid phase extraction is one of the major applications of molecularly imprinted polymers fields for clean-up of environmental and biological samples namely molecularly imprinted solid-phase extraction. In this study, solid phase extraction using the imprinted polymer has been optimized with the experimental design approach for a triazine herbicide, named atrazine with regard to the critical factors which influence the molecular imprinted solid phase extraction efficiency such as sample pH, concentration, flow-rate, volume, elution solvent, washing solvent and sorbent mass. Optimization methods that involve changing one factor at a time can be laborious. A novel approach for the optimization of imprinted solid-phase extraction using chemometrics is described. The factors were evaluated statistically and also validated with spiked water samples and showed a good reproducibility over six consecutive days as well as six within-day experiments. Also, in order to the evaluate efficiency of the optimized molecularly imprinted solid-phase extraction protocols, enrichment capacity, reusability and cross-reactivity of cartridges have been also evaluated. Finally, selective molecularly imprinted solid-phase extraction of atrazine was successfully demonstrated with a recovery above 90% for spiked drinking water samples. It was concluded that the chemometrics is frequently employed for analytical method optimization and based on the obtained results, it is believed that the central composite design could prove beneficial for aiding the molecularly imprinted polymer and molecularly imprinted solid-phase extraction development