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  • Dissertation Conclusions
    URT the CML for groups I and II was the same and slightly increased in the third group The CMD increased from group I to group II and then sharply decreased to group III In the ERT the trend was similar to that of the LRT With the exception of the upper left and right lobes the CML and CMD in the lobes were not dependent on the weight of the lobe nor on its location within the lung Fiber retention in the animals as percent of inhaled fibers were 30 8 1 61 27 1 1 33 and 21 9 1 66 for groups I II and III respectively Fiber retention in the lungs of animals as a whole and in individual lobes increased with increasing fiber length up to 6 5 μm and then decreased with increasing fiber length Retention by diameter peaked at 0 5 μm and rapidly decreased as the diameter increased Retention in the lobes was found to be dependent on the location and the average distance of the lobe from the principal bronchus and trachea and not on the size of the lobe Pulmonary deposition in the guinea pig is higher than that obtained

    Original URL path: http://campus.murraystate.edu/academic/faculty/BAtieh/conclusion.htm (2016-01-26)
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  • Dissertation Highlights
    phase contrast microscopy ANIMAL SAMPLE SIZE Three groups 7 guinea pigs each were determined to be used for this study All three groups were exposed at the same time The reason for this selection was based on a study by Hammad et al 1982 It was reported that the highest observed standard deviation S D median coefficient of variation C V and mean X for fiber retention in 5 rats lungs were 4 76 0 76 and 10 respectively The observed data came from 5 different categories based on diameters and lengths of the fibers Assuming that the mean μ and the median coefficient of variation C V in the overall study were 10 and 0 76 respectively then the standard deviation s would become σ μ C V σ μ C V hence σ 10 0 76 7 60 At a 90 level of confidence Z unit normal distribution 1 645 The next step was to select the width of the interval w Assuming an interval width w of 5 units 1 2 the mean the experiment was designed so that we would be 90 sure that the observed mean X and the actual mean μ would differ by 5 units or less i e μ X 5 Therefore for a standard deviation of 7 6 confidence level of 0 90 and w 5 the minimum size of the animal sample n was calculated by the following equation Daniel 1983 w Z σ n 1 2 which when solved for n gave n Z 2 σ 2 w 2 and therefore n 1 645 2 7 60 2 5 2 6 25 Rounded up to the next largest whole number n became 7 Because the calculated sample size was 7 animals per each group 21 guinea pigs were exposed in this experiment However two of the twenty one guinea pigs died during the exposure leaving 19 animals available for the experiment Because of their odd number the animals were divided into 6 6 and 7 for groups I II and III respectively Further more in the digestion process of the lungs two lobes the accessory right lobe and the middle left lobe of animals 11 and 12 of group II were inadvertently destroyed ESTIMATION OF THE ANIMAL S MINUTE VOLUME The minute volume for guinea pigs have been reported differently by different authors and researchers Crosfill and Widdicombe 1961 reported the minute volume of the guinea pig to be 0 13 l min with values ranging from 0 08 to 0 19 l min These values were measured while the animal was anaesthetized Guyton 1947 on the other hand reported values ranging between 0 10 and 0 38 l min with an average observation of about 0 16 l min Applying the formula described by Guyton the minute volume for guinea pigs of body weight ranging from 0 274 to 0 941 kg with an average of 0 466 kg would be about 210 ml min Guyton 1947 Mauderly et al 1979 and Silbaugh et al 1981 also reported similar values of 0 171 and 0 25 l minute respectively Based on the above reported values estimating a minute volume for the guinea pig of 250 ml min seemed reasonable However the minute volume for each animal was determined and used to calculate deposition in that particular animal Minute volumes were estimated using Guyton s equation Guyton 1947 Minute volume for any individual lobe of a lung was also estimated as percentage of the animal s M V in the same ratio of lobe weight to total body weight Hammad and Rowhani 1984 ESTIMATION OF THE EXPOSURE DUST CONCENTRATION Hammad 1982 in an inhalation study on rats exposed to ceramic fibers reported that the mean airborne fiber concentration was 303 with a standard deviation of 17 fibers cc of air Rowhani 1982 reported that the dust concentration in rats was 709 fibers cc of air For this study the exposure dust concentration was estimated to be about 300 fibers cc of air This number was reached by the following assumptions and calculations Assumptions 1 about 5 fibers would be counted per field 2 the area of the field was 1 12225x10 3 mm 2 3 the actual collection diameter of the 47 mm diameter membrane filter used for the recovered fibers from the animal lung was 35 mm thus making its effective collection area 962 11 mm 2 4 the actual collection diameter of the 37 mm diameter membrane filter used for the dust sampling in the chamber was 35 mm thus making its effective collection area 962 11 mm 2 Therefore the number of fields per filter would be 8 57x10 5 Hence the number of fibers estimated per filter would be approximately 4 285x10 6 Fibers per filter were determined by multiplying the concentration fiber cc by duration total minutes of exposure by minute volume ml min by percentage deposition in the alveolar tissue That is fibers filter C duration minute volume deposition For an average minute volume of 250 ml minute for guinea pigs and a percentage deposition in the alveolar tissue of about 10 15 estimated from other studies Raab et al 1977 and Rowhani 1982 the concentration in the exposure chamber for 6 hour exposure would be then expected to be approximately 317 fibers ml of air Considering the air flow rates entering the exposure chamber as follows 1 generation air 10 liters min that took the fibers through the elutriator and into the chamber 2 dilution air 40 liters min that diluted the dust cloud before entering the chamber The dust concentration generated by the dispenser and carried by the generation air would be then approximately 1500 fiber ml of air Sampling time per filter was then determined by equally dividing the entire time of exposure by 4 the number of air samples thus yielding 90 minutes for each DESCRIPTION OF THE EXPOSURE TECHNIQUE All animals were exposed to the dust cloud by nose only Exposure was as described in section D above The animals were exposed for a total of six continuous hours Following exposure the animals were divided and scheduled to be sacrificed SURVIVAL TIME Morgan et al 1977 reported that there was a rapid fall clearance t 1 2 1 day in the lung fiber contents assuming that this decline represented mucociliary clearance of the airways Hammad et al 1982 on the other hand showed that the alveolar clearance was a slow process t 1 2 40 days This clearly showed that clearance in the lungs occurs in two compartments the ciliated and the non ciliated airways To be able to account for these two types of clearances in this experiment group I was sacrificed immediately after exposure group II 24 hours later and group III 5 days after exposure ANIMAL SACRIFICE Animals were anaesthetized by sodium pentobarbital 50 mg Kg Nembutal In order to reduce organic material and mass that could interfere with microscopic examination of fibers recovered from the lungs the blood content of the lungs was removed by perfusion The abdomen was opened a catheter inserted into the right ventricle and the descending aorta transacted A saline heparin solution was infused for three minutes at 15 cm water pressure to clear the lungs The lungs were further infused with fixative solution Karnovesky s for 3 minutes The trachea and the lobes of the lungs were then carefully separated and placed in preservative tubes The nose was then washed 3 times with 10 ml of saline and the collected wash fluid was added to the trachea s tube All samples were then stored until digestion and preparation for microscopic counting PREPARATION OF THE LUNGS FOR FIBER COUNTING Tracheae and lung lobes were all digested in the same manner The lobes of each animal were weighted prior to digestion All digestion procedures for any sample were carried out in one tube so that the possibility of losing fibers was minimized After placing each lung tissue in a separate tube Clorox bleach sodium hypochlorite was added All tubes were tightly closed and left overnight at room temperature If some of the tissue was not digested completely more Clorox was added and the tube was agitated gently on a shaker until all the tissue was completely digested The resulting solution was then washed with distilled water from the tube onto a 47 mm membrane filter with a pore size of 0 22 μm The tube was rinsed with isopropanol and poured over the filter The isopropanol was used to dissolve colloidal particles in the solution and thus yielded a better distribution of fibers on the filter After this the tube was washed with xylene and transferred to the filter This was necessary to remove any fats and other organic soluble tissue materials from the filter without affecting the fibers Afterwards the filters were dried for about 1 day at room temperature and made ready for counting COUNTING OF RECOVERED FIBERS A fiber is defined as a particle whose length is at least three times greater than its diameter A wedge of the dried prepared filter section L was cut with an arc of about 1 cm and placed on the edge of a clean glass slide A drop of mounting medium was placed on the center of the slide with an applicator and smeared with a tooth pick into the shape and size similar to that of the wedge With forceps the cut wedge was then repositioned to the center of the slide and placed on the mounting medium with the dust side up Care was taken not to wash off the fibers by excess amount of the medium A cover slip No 1 was then placed on top of the wedge A drop of immersion oil was applied All slides were counted with phase contrast 10X eyepiece fitted with a calibrated Porton graticule and 100X objective 1 30 N A for a total magnification of 1000X The Porton graticule was calibrated against a stage micrometer The diameter D of the circles located above the large rectangle of the graticule was determined by applying the following equation D L 2 N 1 2 where L the length of the rectangle measured by the stage micrometer 200 and N is the number of that circle Microscopic fields were then selected at random and each examined from left to right right to left and top to bottom Slides with uneven distribution containing more than 25 fibers per field were disregarded and new prepared slides were counted instead Fiber diameters were measured between circles number 1 and 8 while fiber lengths were measured between circle number 4 up to and including circle number 16 Mid size of the interval between any two circles was used to calculate the median length and the median diameter of the fiber distribution Fibers which were inside the reticle or entered it from any side were counted and sized Fibers with any portion extending outside the reticle were counted as half fibers Number of fields and fibers counted per each sample air or animals was a function of lobe size and size of filter used As a result an average of 800 fibers were counted in 200 fields for each air sample and 800 1000 fibers in 250 450 fields per each animal sample DEFINITION OF TERMS Nineteen male Hartly albino guinea pigs were utilized in this study Animals were divided into groups I II and III with 6 6 and 7 animals respectively Animals were assigned numbers from 1 to 19 The respiratory tract of the animal was divided into two compartments the upper respiratory tract URT for trachea and nose and the lower respiratory tract LRT for the lungs Both URT and LRT were referred to as the entire respiratory tract ERT Further division of the lungs was as the following UR upper right lobe right cranial middle lobes AR accessory right lobe right accessory lobe LR lower right lobe right caudal lobe UL upper left lobe left cranial lobe ML middle left lobe left middle lobe LL lower left lobe left caudal lobe RESULTS BODY WEIGHT EFFECT All animals showed little if any effects of the exposure on their body weight Mean body weight for group I did not change at all during the six hours exposure However groups II and III showed a slight reduction The mean body weight for both groups at time of sacrifice was respectively 1 25 2 21 less than that at time of exposure LUNG WEIGHT Correlation between body weights and lung weights indicated that the two parameters have a strong relationship and that the weight of the lungs is highly dependent on the animals body weight MINUTE VOLUME M V Minute volume for each guinea pig was estimated by Guyton s equation which relates the M V to the body weight Minute volume for each animal was estimated at time of exposure Minute volumes for lobes were also estimated Minute volumes used to calculate retention of fibers in the lobes of an animal were those M V s estimated for that animal Mean minute volumes calculated for the entire group were not used in calculating retention CONCENTRATION AND SIZE DISTRIBUTION OF FIBERS IN THE EXPOSURE CHAMBER Concentration The overall time weighted concentration of airborne fibers in the exposure chamber was 297 25 5 fiber ml air for the entire period of six hours Concentrations determined by the four air sampling filters 90 minutes each were 327 295 265 and 302 fiber ml Size Distribution The means of the count median length MCML and the count median diameter MCMD of airborne fibers in the exposure chamber were 13 3 μm and 0 92 μm with geometric standard deviations GSD of 2 64 and 1 96 respectively CONCENTRATION AND SIZE DISTRIBUTION OF FIBERS IN ANIMALS Concentration Fibers counted in animals were recovered from two compartments LRT and URT The sum of fibers counted in the two compartments was reported as total number of fibers in the animal or ERT The average total number of fibers recovered from the entire respiratory tract ERT of groups I II and III were 8 5x10 6 7 28x10 5 7 6x10 6 5 62x10 5 and 6 2x10 6 6 9x10 5 fibers animal respectively Size Distribution The MCML and MCMD of fibers recovered from the lungs LRT slightly decreased from 10 6 μm and 0 76 μm in the first group to 9 95 μm and 0 75 μm in the second group to 9 25 μm and 0 71 μm in the third group In the URT the MCML slightly increased from groups I and II to group III i e from 14 1 μm in groups I and II to 15 5 μm in group III The MCMD increased from 0 88 μm in the first group to 0 91 μm in the second group and sharply decreased to 0 69 μm in the third group The MCML and MCMD for the ERT showed trends similar to those of the LRT FIBER RETENTION IN ANIMALS The overall mean retention with S D for the LRT was 28 5 1 44 for group I 25 8 1 05 for group II and 21 9 1 62 for group III For URT these values were 2 25 0 484 1 30 0 425 and 0 078 0 008 and for ERT retention was 30 8 1 61 27 1 1 33 and 21 9 1 66 respectively Assuming that the average number of fibers of all sizes recovered from group I represents 100 retention zero clearance then the overall retention percent in the LRT of groups II and III are 91 1 and 78 5 respectively In the URT relative retention in groups II and III are 59 0 and 3 58 and that in the ERT are 89 4 and 72 9 CONCENTRATION AND SIZE DISTRIBUTION OF FIBERS IN LOBES AND TRACHEAE Concentration The average number of fibers recovered from the lobes and tracheae of animals in group I ranged from 1 40x10 5 3 42x10 4 in the ML lobe to 1 88x10 6 2 28x10 5 in the LR lobe Lobes of groups II and III showed similar trends with lowest number of fibers counted for ML lobes and highest number of fibers counted for LR lobes In groups I and II the number of fibers counted in the trachea was considerably higher than the number of fibers counted in the trachea of the third group The average number of fibers ranged from 6 14x10 5 in the first group to 2 2x10 4 in the third group Size Distribution Results indicated that the CML and CMD were not dependent on the weight of the lobe FIBER RETENTION IN LOBES AND TRACHEAE Results clearly showed that the mean retention of fibers in the upper left lobe UL in all three groups was the highest Fiber retention in the lobes indicated that retention was not dependent on the weight and size of the lobe but on the position of the lobe within the respiratory tract as indicated later in section I below The average number of fibers counted per lobe however indicated that retention consistently decreased from group I to group III implying some clearance over time The same is true for fiber retention in the trachea However clearance in this compartment of the respiratory tract was much more rapid The average number of fibers dropped from 6 14x10 5 in the first group to 3 62x10 5 in the second group and to 2 20x10 4 in the third group EVENNESS INDEX E I FOR FIBERS RETAINED IN LOBES The evenness index was determined for all lobes of the animals in the three groups to eliminate the effect of lobar weights on fiber retention The evenness index for any lobe was calculated by dividing the fiber concentration number of fibers per

    Original URL path: http://campus.murraystate.edu/academic/faculty/BAtieh/thesis.htm (2016-01-26)
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  • OSH 450, Syllabus
    of reasonable accommodations for disabled employees Objectives Develop an equipment checklist based on the Americans with Disabilities Act ADA Accessibility Guidelines Ruler Tape measures Force gauge and light meter Use your checklist to evaluate compliance with the Guidelines Evaluate a building on campus or alternatively a government facility Select one job performed in this building and provide examples of reasonable accommodations that employers may be expected to provide for a disabled employee F Environmental Sciences Ventilation Related Laboratory Air Velocity and Flow Measurements Pitot tubes Inclined manometers Magnehelic gauges Face velocity velometers Ventilation Evaluation Table saw hood Laboratory fume hood Water and Wastewater Related Laboratory Water Testing Free residual chlorine waterborne diseases Ammonia and nitrates eutrophication Dissolved oxygen oxygen depletion G Student Individual Research Efforts and Presentations Students will be required to research the following and present their finding in written reports and class presentations Reports and presentations should include when if applicable Principal applications Structure determination for identifying organic and inorganic compounds General quantitative analysis Molecular phenomenon Advantages in qualitative analysis Advantages in quantitative analysis Average sample desired for qualitative analysis Method limitations Sample limitations Analytical methods OSHA NIOSH recommended methods and standards Alternative methods and approaches Advantages and disadvantages of recommended proposed methods Topics to Consider Instrumentation Infrared Spectroscopy Ultraviolet Visible Spectrophotometry Combined Gas Liquid Chromatography Including Ion Exchange and Thin Layer Mass Spectrometry X Ray Diffraction Atomic Absorption Emission Spectroscopy Analytical Methods and Comprehensive Laboratory Analysis Biological Agents Chemical Agents Physical Agents Instructional Activities Lectures Handouts Lab sessions Homework Field Clinical and or Laboratory Experiences Field application and equipment demonstration In class demonstration of all instruments and equipment discussed during lectures However students are encouraged to utilize the industrial hygiene laboratory for more hands on Text s and Resources Handouts by topic subject when applicable Lecture notes Evaluation and Grading Procedures Attendance participation 25 Faculty assignments evaluations 50 Lab analysis project PowerPoint presentation 25 Project contents 10 PowerPoint presentation 15 The final grade for the course is determined by contributing faculty input and evaluation Attendance Policy Attendance is required Unexcused absences may affect your final grade for the course Academic Honesty Policy Murray State University takes seriously its moral and educational obligation to maintain high standards of academic honesty and ethical behavior Instructors are expected to evaluate students academic achievements accurately as well as ascertain that work submitted by students is authentic and the result of their own efforts and consistent with established academic standards Students are obligated to respect and abide by the basic standards of personal and professional integrity Violations of Academic Honesty Include Cheating Intentionally using or attempting to use unauthorized information such as books notes study aids or other electronic online or digital devices in any academic exercise as well as unauthorized com munication of information by any means to or from others during any academic exercise Fabrication and Falsification Intentional alteration or invention of any information or citation in an academic exercise Falsification involves changing information whereas fabrication involves inventing or counterfeiting

    Original URL path: http://campus.murraystate.edu/academic/faculty/BAtieh/osh450.htm (2016-01-26)
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  • Dr. Atieh's Grading System
    TEST II 25 FINAL EXAM 25 OSH 450 PRACTICAL APPLICATION LAB ATTENDANCE PARTICIPATION 25 FACULTY ASSIGNMENTS EVALUATIONS 50 LAB PROJECT 25 PROJECT CONTENTS 10 PROJECT PRESENTATION 15 OSH 591 ENG TECH ASPECTS OF SAFETY ATTENDANCE PARTICIPATION 20 INDIVIDUAL TEAM EFFORT 20 PROJECT REPORT 30 PROJECT PRESENTATION 30 OSH 621 IND HYGIENE SAFETY PROGRAM DEVELOPMENT HOMEWORK 15 PAPER 20 CRITIQUE 15 FINAL EXAM 50 PAPERS AND CRITIQUES ARE DUE ON POSTED

    Original URL path: http://campus.murraystate.edu/academic/faculty/BAtieh/grades.htm (2016-01-26)
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  • Dr. Atieh's Office Hours
    15 OSH 626 01 INDUSTRIAL HYGIENE SAMPLING STRATEGIES MONDAY 18 00 21 00 OSH 637 01 BIOSTATISTICS PROBABILITY TUESDAY 14 00 17 00 OSH 687 01 WASTEWATER TREATMENT THURSDAY 18 00 21 00 OFFICE HOURS MONDAY WEDNESDAY 10 00 14 00 TUESDAY THURSDAY 09 00 10 30 FRIDAY OFFICE HOURS BY APPOINTMENT ONLY OFFICE HOURS MAY VARY DUE TO OTHER UNIVERSITY ACTIVITIES OTHER OFFICE HOURS ARE AVAILABLE ONLY BY APPOINTMENT

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  • Dr. Atieh's Off-Campus Schedule
    Class Meetings 1st meeting is on location day date and time set by MSU Check your classes schedule bulletin for location Meetings for the rest of the semester will be

    Original URL path: http://campus.murraystate.edu/academic/faculty/BAtieh/offcampus.htm (2016-01-26)
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  • Dr. Atieh's Final Exams Policy & Schedule
    a final exam will automatically receive an I for the course Upon completion and making up for the missed final the student s grade will be adjusted and cannot exceed a B for the course Any student with a B grade or less who for any reason misses a final exam will automatically receive an E for the course Spring 2016 Final Exams Schedule OSH 425 01 PHYSICAL AGENTS TUESDAY

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  • Industrial Hygiene I
    40 35 50 43 OSH 420 HOMEWORK SET 2 1 A worker was exposed to 90 dB for 3 hours and 95 dB for the rest of his 8 hour shift Determine the dose for that day s exposure 2 Given the following exposure schedule calculate the dose and the time weighted average Exposure Level dB Exposure Time hr 90 3 0 95 1 5 85 2 5 90 1 0 3 The length of a sound wave was measured to be 56 3 with a frequency of 1000 Hz Determine the nature of the medium through which this sound wave was propagated 4 Find the sound pressure level generated from three sources each measuring 90 dB 5 Determine the allowable exposure time for a noise source having an SPL of 88 dB 6 Calculate the TWA for an exposure dose measured to be 130 OSH 420 HOMEWORK SET 3 1 The average power output of 6 562 ft diameter antenna is 5000 watts The waves are emitted at a frequency of 10 GHz Find the power density at 50 100 meters from the source 2 If an isotope loses 35 of its initial activity in 2 days calculate the half life for this isotope in hours 3 A radioactive isotope has an original activity of 10 Ci Calculate its activity after 5 days if this isotope has a t 1 2 14 96 hours 4 Calculate the initial activity of an isotope in Ci if its measured activity three days after its preparation is 50 Ci and it has a half life of 72 hours 5 A gamma source has a dose rate of 125 R hour at 1 5 meters Determine its dose rate at 4 5 meters from the source 6 A gamma ray has a linear

    Original URL path: http://campus.murraystate.edu/academic/faculty/BAtieh/hw420.htm (2016-01-26)
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