Evaluation of Digits-in-Noise Test and Hearing Handicap Inventory for Adults Screening in Patients with Occupational Noise-Induced Hearing Loss

Objective:To explore the clinical evaluation role of the Digits-in-Noise(DIN)test and Hearing Handicap Inventory for Adults Screening(HHIA-S)for patients with occupational noise-induced hearing loss and to observe and analyze their application values.Methods:Fifty patients with suspected occupational noise-induced hearing loss were randomly selected from the Department of Otolaryngology at the hospital as the research target.The collection period for the research cases spanned from January 2022 to November 2023,and all patients had a history of noise exposure.The DIN test and HHIA-S were used for hearing examinations,with clinical,comprehensive diagnosis serving as the gold standard to study their diagnostic performance.Results:The compliance rate of the DIN test was 88.00%,the HHIA-S’s compliance rate was 80.00%,and the combined compliance rate was 94.00%.The compliance rate of the DIN test and the combined compliance rates of the patients were statistically significant compared to the clinical gold standard data(P<0.05),while there was no difference between the compliance rate of the HHIA-S and the gold standard(P>0.05).The data shows that the sensitivity of the combined diagnosis is significantly higher than the sensitivity data of the DIN test and HHIA-S examination alone(P<0.05).Its specificity is 100.00%,and the accuracy data of the joint diagnosis in the degree were higher than those of the DIN test alone(P>0.05)and the HHIA-S alone(P<0.05).Conclusion:For patients with occupational noise-induced hearing loss,the joint evaluation of the DIN test and HHIA-S can significantly improve their diagnostic value with high sensitivity and accuracy.

Portable 4-Channel Electrochemical Noise Test System

A portable 4-channel electrochemical noise(EN) test system with high precision was developed.The modular instrument cRIO was used as its core and the signal conditioning module included zero resistance ammeter(ZRA),fly line,screening box and shielded wire.The EN data were acquired from two Q235 carbon steel specimens placed in 0.5 mol/L H2SO4 solution and 0.1 mol/L NaCl solution.The experimental result shows that this system can achieve an accuracy of 10 pA and 10 μV,and it can be applied to on-site multi-channel EN test.

Noise test of two manufactured power tillers during transport on different local road conditions

Hearing injury due to exposure to excessive noise during general farming activities is a significant problem for farmers.The present investigation was carried out for better understanding of the noise propagation trends,as well as noise attenuation characteristics of the two different developed power tillers on different surfaces in transportation under Egyptian conditions.In Egypt,the agricultural roads are one of the main problems that limited the usage of farm machinery.In the last few years,it is noticed that the manufacturers and farmers in Egypt applied the diesel engine of command irrigation pump as the source of power for the manufactured power tillers.Besides their on-farm application in Egypt,they are also engaged in transportation of agricultural products and human beings on the asphalt,and dirt rural roads.In spite of their adverse effects due to noise on operators and bystanders,limited information is available concerning the noise investigation of these manufactured machines.The aim of this research was to evaluate the noise propagation trends as well as noise attenuation characteristics of the manufactured power tillers on different surfaces in transportation conditions.The developed power tillers that used in this study were fitted with approximately 6 kW(8 hp)and 7.5 kW(10 hp)diesel engines for two different tillers transport machines.During measurement and recording the sound pressure signals of the power tillers,the variables of engine speeds and gear ratios were varied to cover the most normal range of the power tillers operation in transportation conditions for the asphalt and dirt rural roads.The test sites were prepared according to SAE noise measurement test procedures.The maximum overall noise measured at driver ear’s position at different gear ratios in asphalt,and dirt rural roads were about 98.2 and 92 dB(A)for 1,350 r/min engine speed which is higher than allowable noise exposure prescribed by National Institute for Occupational Safety and Health[1].