Industrialization has had many complications for human beings and has been a threat to social mental and physical health. Vibration induced noises in the workplace is one of the main devastating factor in producing hearing loss in workers.Recently, several investigations on the issue of noise pollution and noise dosimetry and also Noise induced hearing loss have been developed. In the current article we will have a look and sometimes reconsideration on the results and of these studies and will discuss the findings in regard to noise control and management in details.

Technology has made people to be exposed to a lot of sources of noise because of the instruments they use at workplace or at home. Dentists are a group of such people who are especially subject to different sources of noise such as high-speed air-turbine headpieces, operated at 300,000 to 400,000 revolutions per minute In the current study we were aimed at measuring noise at the dentists&apos office estimating hearing thresholds in dentists and determining the reason of hearing loss and finally determining the role that work experience e play in the hearing loss occurred.Dentists have been divided into groups based on the work experience and subjects were randomly selected from the dentists of various groups. Sound levels were measured in clinical settings and in a pre-clinical laboratory for estimation of hearing-damage risk among dentists,The findings demonstrated that all dentists regardless of age and gender suffered a notched hearing loss at 6000 Hz. Additionally hearing loss was worse in right ear.Since sound energy of high-speed air-turbine headpieces is mostly concentrated in high frequencies, it can lead in the most possible hearing loss at 6000Hz.

We measured the noise caused by Vehicles and its subjective effects in the Modarres high way In Tehran. we examined 143 cases in 11 stations in the mentioned pathway with an accuracy of 95%  and a standard deviation of 39%. The noise criteria of Leq and the number of vehicles were determined in dBA. The loudness contours were also measured in some stations to determine the subjective impacts of noise. Then the correlation of the responses of the interviewees with sound pressure level was measured. Based on our findings, decrease of  the noise of traffic sources should be considered three levels: the first level is noise reduction at the level of source, e.g. the vehiclesthe second is Noise reduction at the traffic level and the third is noise reduction at the level of general activity.

Objective: Noise measurement and frequency analysis of commercially available noisy toys were the main purposes of the study.
Materials and Methods: 181 noisy toys commonly found in toy stores in different zones of Tehran were selected and categorized into 10 groups. Noise measurement were done at 2, 25, and 50 cm from toys in dBA. The noisiest toy of each group was frequency analyzed in octave bands.
Results: The highest and the lowest intensity levels belonged to the gun (mean=112 dBA and range of 100-127 dBA) and to the rattle-box (mean=84 dBA and range of 74-95 dBA), respectively. Noise intensity levels significantly decreased with increasing distance except for two toys. Noise frequency analysis indicated energy in effective hearing frequencies. Most of the toys energies were in the middle and high frequency region.
Conclusion: As intensity level of the toys is considerable, mostly more than 90 dBA, and also their energy exist in the middle and high frequency region, toys should be considered as a cause of the hearing impairment.

Background and Aim: In recent years, attention of the health care managers is attracted to three factors including promotion of services quality, accessibility and procurement of financial resources of relevant organizations. The aim of this study is to consider the executive status of guideline of managed health care for preoperative assessments of ENT patients at Bazarganan Hospital in 2005.
Materials and Methods: The present research is conducted on 140 cases in descriptive form. The research information is collected by using a check list. Indexes and method of descriptive statistics are used for the data analysis and statistical study.
Results: Of one hundred and forty ENT patient records, in 136 (97%) of the cases American Society of Anesthesia criteria had been registered. Vital signs, patient histories and CBC were recorded in 137 (98%), 138 (99.5%) and 139 (98.3%) patients recordes, respectively. Eight (69.7%) over 60 years old cases had been X-rayed. EKG has been performed on all fifteen cases over 40 years old. Thirty nine (28%) recordes contained internist and cardiologist counselling.
Conclusions: Assessment of guidline indicates very good status. Application of managed care guidelines of preoperative assessment in ENT surgeries could play a crucial role in reducing complication of ENT surgeries and the improvement of the implication of the guidelines.