جستجوی مقالات مرتبط با کلیدواژه "ventilation system" در نشریات گروه "پزشکی"

Cadmium is one of the heavy metals and long time exposure to it can cause a lot of health problems in human beings. In this study, we investigated the toxic effects of Cadmium on kidney performance in the smokers and non-smokers and also its relationship with ventilation systems at Maragheh City prison.

This descriptive-analytical study included 90 prisoners. Cadmium of urine samples was measured by using a graphite furnace atomic absorption spectrometer. Parameters of renal function including urine specific gravity, creatinine, protein, albumin, glucose and urea were measured using a Hitachi autoanalyzer.

The highest values of excretion of cadmium, protein, albumin, per gram creatinine and glucose were observed in the smokers without ventilation systems in their living quarters. In this group, ratio of cadmium per creatinine showed significant relationships with protein per creatinine, albumin per creatinine, urea, and glucose (P < 0.05), while in the control group without ventilation, this ratio had significant relationship only with urinary glucose excretion (P < 0.05) and we found no significant relationships between cadmium per creatinine ratio and other variables in this group (P ≥ 0.05).

Exposure to cadmium metal through cigarette smoke can directly and indirectly affect kidney function and lead to increased excretion of protein, albumin, urea and glucose. This effect is also affected by indoor ventilation systems, so that the presence of proper ventilation systems reduces exposure to cigarette smoke and hence cadmium, which results in reduced harmful effects of cadmium on the renal function of the exposed individuals.

the importance of clean air is well known in industrial environments. Industries used in numerous Chemicals that many of them are toxic. Proper industrial ventilation can create a sense of calm and comfort for the staff, as a result of which the staff performs well and will have a positive impact on their performance. This study was aimed to determine the concentration of air pollutants in unit abrasive vitrified and local ventilation system design appropriate to reduce the concentration of particles.

This study was cross – sectional that conducted in one metal industry in three phases. First step: Investigate and determine of planning workshops and of pollutants produced location, second stage: sampling and determining the concentrations of contaminants, the third stage: Design of local ventilation system.

According to the standard, the occupational exposure limits for chromium and nickel in the workplace are 0.01 and 0.1 mg / m3, respectively. The concentration of chromium and nickel in the plating room was lower than the permissible concentration. while the concentration of particles in the grinding section 1 and 2 over the permissible level and as 11.75 and 13.62 mg / m3, respectively. The local ventilation system was designed according to speed pressure method for grinding unit.

Local ventilation system is designed the possibility of particles capture and control to be effective in the machining salon of grinding section.

One of the most important factors impacting the performance and efficiency of production is ventilation that plays this crucial role with reduction the pollution and heat. The purpose of the present article is to determine the impacts of improving the ventilation systems on performance and efficiency of production through controlling the physical parameters such as temperature and moisture and also with controlling the chemical factors of workplace in Autoconer unit of a spinning company.
Research data have been assessed using dry thermometer, wet thermometer and digital humidity thermometer measuring environmental parameters. These parameters have been used to evaluate the thermal discomfort indicators (DI). The sampling was performed using NIOSH-0600 protocol by aluminum cyclone and 25 mm PVC filter. Using Gravimetric analysis method through a scale with an accuracy of 0.0001 gr data related to concentration of the polyester and cotton pollutant dusts, respirable dust, have been assessed. Obtained data from measuring the concentration of pollutants have been used to estimate the effectiveness of ventilation systems. The amount of the production has been assessed by multiplying of measuring the reel samples and number of reels or spring-enabled device to ascertain the efficiency of production. All of the investigations and comparisons have been conducted in three conditional situations including without suitable ventilation system, improved and adjusted ventilation system and finally designing and installing the new ventilation system; in the all of the stations of Autoconor unit.
Results of the study indicated that the amounts of DI in three investigated saloons didn’t have significant differences and all of them were close to thermal comfort (P=0.45); and despite of exert small changes, it has not been observed significant differences between thermal discomfort indicator (DI) with process of improving air conditioning (P=0.42). On the other hand, it has been determined that improving the ventilation system by reduction the pollutants, increased the production and efficiency of the work (P 0.05).
The present study shows that improving ventilation system through controlling the chemical parameters and physical parameters, with lower impacts; including temperature and moisture will have an important role in increasing the operation and efficiency of production in spinning industry.

Hospital indoor air contains a wide range of airborne pathogenic bioaerosols which have a significant impact on health care staff’ health and welfare. The aim of this study was to assess the effects of ventilation system types on occupational exposure of the health care staffs to airborne bioaerosols in the isolation room based on the patient bed arrangements and the standing locations of the health care staff. Personal exposures were measured based on five given types of ventilation system, 2 patient bed arrangements (at a corner and in the middle of the room), and two different standing locations for the health care staff (standing close to the patient’s bed, and down a side section of the bed). For personal sampling, filtration method recommended by th e American conference of governmental industrial hygienists(ACGIH) was used. The highest exposure to airborne bioaerosols was observed when the ventilation system was switched off. There were significant decreases in the bioaerosols concentration after using all types of ventilation system (P value <0.001). The ventilation capacities of 12 air changes per hour showed the best results. No significant differences were found between the bioaerosols concentrations based on the patient bed arrangements as well as the standing locations of the health care staff s (P value > 0.05). The most effective ventilation system for decreasing health care staff’ exposures in the isolation room was associated with supplying of air from a circular grill located on the northern wall and exhausting it through a linear slot located on the southern wall (type 1) with the ventilation rate of 12 air changes per hour.