اخبار و اعلانات
آمار
| تعداد نشریات | 209 |
| تعداد شماره‌ها | 5,456 |
| تعداد مقالات | 60,064 |
| تعداد مشاهده مقاله | 98,721,987 |
| تعداد دریافت فایل اصل مقاله | 78,785,088 |
ارزیابی میزان تراکم الیاف آزبست در هوای حوزه تنفسی کارگران و در فضای یک محیط صنعتی | ||
| محیط شناسی | ||
| مقاله 1، دوره 18، شماره 18، دی 1376 اصل مقاله (944.46 K) | ||
| نویسندگان | ||
مهندس شهره خرد پیر؛ دکتر فتح الله مضطرزاده؛ دکتر منصور غیاث الدین 
| ||
| کلیدواژه‌ها | ||
| آزبست؛ آستانه مجاز؛ الیاف زیان آور آزبست؛ آلودگی هوا؛ حوزه تنفسی؛ سیمان؛ شیفت کار؛ نسبت طول به قطر | ||
| عنوان مقاله [English] | ||
| - | ||
| چکیده [English] | ||
| Occupational exposure to hazardous asbestos fibers on the basis of Amercian Society for Testing and Materials criterion (length> 5mm, diameter < 3,um and length/diameter_5:1 ) were monitored in an asbestos - cement factory for the first time in the country. By evaluating personal (from worker's breathing zone) and environmental samples (from plant's atmosphere) asbestiform fibers were counted and calculated as fiber/ml (f/ml) by Phase Contrast Optical Microscope. On the basis of 8-h time weighted average or its equivalent, average fiber levels and range of concentrations III each unit of workshops as well as, environmental concentrations were determined. The results indicated that 83.3% of workers are exposed to levels exceeding the Threshold Limit Value (TL V =0.2 F/ml) and all the studied workshops were considered as fiber emission sources (5-13 times the TL V). Test statistic on mean with 95%. Confidence showed no significant difference between two finishing workshops, long and short pipes (? =0.05, to.975,9). In addition, 8-h daily shift duration exposures on average are less than half of that observed in the 12-h shift. Test statistic with 95% confidence showed significant difference between mean exposure of daily shift durations (? =0.05, t095,17). | ||
| کلیدواژه‌ها [English] | ||
| Air pollution, Asbestos, Asbestos Fibers, Breathing Zone, Coment, Hazardous, Length per Diameter Ratio (LID), Threshold Limit Value, Work Shift | ||
|
آمار تعداد مشاهده مقاله: 2,768 تعداد دریافت فایل اصل مقاله: 1,172 |
||
