SUMMARY The study aimed to evaluate, through the use of the EA-RfitTM Validation System, the real reduction (PAR) for the right ear (AuD), for the left ear (AuS) and biaural reduction related to each of the seven earplugs currently produced by 3M. In addition, we wanted to verify any difference between the aforementioned PARs in consideration of the tendency to predominantly use the right hand (right-handed) or the left hand (left-handed) and in relation to gender. Finally, for each insert and for each subject, an audiometric examination was conducted with the insert worn, to compare the average PAR value obtained by the EA-RfitTM system for each of the seven inserts and for all selected subjects, with the determined abatement curve through the audiometric measurement of the hearing threshold with the insert worn. The use of the E-ARfitTM system for the choice of the ear insert leads to important advantages in the protection of all workers. Moldable acoustic PPE generally proved to be more efficient than non-moldable, so much so that the higher SNRs (provided by the manufacturer), especially when referring to non-moldable inserts, were found to be misleading as to the real personal abatement capacity of the inserts. The average audiometric curves, obtained with the different inserts worn, confirmed that all of them guarantee a higher reduction for high frequencies than for social ones.

BACKGROUND Laboratory levels of perceived noise attenuation as heard using earplugs are always higher than the real levels that can be achieved at the workplace. The employer is bound by law to supply individual hearing protection devices (HPDs), to assess their efficiency and efficacy, and also to inform and train workers on the correct use of HPDs. OBJECTIVES This study assessed the real "personal attenuation rating" (PAR) of HPDs  used by workers at the workplace, before (PAR A) and after (PAR B) specific and individual training. These values were also compared with the theoretical  "single number rating" (SNR) provided by the manufacturer. METHODS The study covered all the 65 male employees of an awnings factory, using the E-A-RfitTM computerized method, which can measure PARs, based on the difference between sound pressures recorded by an "outside" microphone and an "inside" microphone placed in the auditory canal, with earplugs inserted, before (PAR A) and after (PAR B), i.e., the specific and individual training described above. RESULTS/CONCLUSIONS PARs B were always definitely higher than PARs A, both for all tested frequencies and the corresponding average values, which were automatically detected by E-A-RfitTM. Furthermore the same PARs B were  decidedly lower than the respective SNRs supplied by the manufacturer on the basis of laboratory assessments. These data prove that specific and individual training for workers improves the performance of earplugs, contributing to a more appropriate secondary prevention of the effects of noise on hearing; they also prove that the real attenuation recorded in workers are always lower than those supplied by the manufacturer of the devices. It is recommended that the E-A-RfitTM system, which allowed these results to be achieved objectively, should be normally used to assess exposure to noise in workers, when HPDs are worn.

BACKGROUND The assessment of efficiency of hearing protection devices (HPDs), conducted above statutory limits, must be made using a standardized method while devices are worn; however, standardized and suitable laboratory conditions are difficult to encounter at the workplace. To overcome this problem, there are methods of measurement at the workplace such as "field-microphone-in-real-ear" (F-MIRE). OBJECTIVES The study was concerned with the measurement of real noise attenuation using earplugs and a new evaluation system: we checked the difference between "real" attenuation (at workplace) and "theorical" attenuation (reproduced in the laboratory) as stated by the manufacturer. METHODS We used the E-A-Rfit computerized method, which measures the loss of attenuation of earplugs in the ear, calculating the difference of sound pressure between an "outside" microphone and an "inside" one, in relation to the same earplug. The measurements at the workplace were carried out on eight subjects with good hearing levels (aged between 20 and 25 years), who were trained to wear the devices correctly. After the tests carried out with the E-A-Rfit system, which does not require a subjective answer, we obtained graphs and tables showing real noise attenuation. RESULTS/CONCLUSIONS We propose a comparison between hearing threshold for frequency, personal attenuation rating (PAR) and single number rating (SNR, provided by manufacturer): a difference of 10 dB (PAR 27 db vs. SNR 37 dB) was clearly evident although dissimilar methods were used to obtain such values. The instrument is rapid, simple and objective to use and also allows personalized information and training for every worker.

Our study has examined the valuation of exposure to dust, noise and hand-arm vibrations (HAVs) during "extra-professional" activities of do-it-yourself, like wood smoothing, considering a group of 8 heterogeneous volunteer subjects (not expert of the sector), to find any kind of variability among the subjects. The results have shown a moderate risk for dust exposure and a realer one for HAVs, also higher noise exposure levels when an aspiration system is added to the sander. It's important that the exposure time considered in this study is not comparable to professional time exposure, cause of the "domestic" feature of this activities. Moreover, data could be influenced by different use conditions, grip and material grounds. It's also significant that there are not controls, formation and information of the subjects about the health risks, as well as ipersusceptibility.

This work pertains to the study of exposure to air pollution and noise, of any citizen, in any time of day, within the perimeter of the Polyclinic of Bari. We utilized "dynamic" samplings, in a period of 24 hours, along a walking trail that lasted about 70 minutes, divided on the roads inside the general hospital, performed by voluntary people carrying, by shoulder, a bag containing necessary tools, with their sample heads placed externally in the respiratory area. The values of the environmental survey revealed, particularly, the presence of atmospheric concentrations of PM10 of 63,4 microg/m3 as average value of the whole day and 93 microg/m3 as maximum average value in one hour, far above the limits expected by law for the protection of human health (maximum average value of 50 pg/m3 in 24 hours), almost the whole day and in all areas interested in this study. Also data related to noise showed steady and marked exceeding the limits (average of 68,2 dBA in the morning and 68,0 dBA in the afternoon, versus the limit of 50 dBA by day for hospital areas; average of 65,9 dBA in the night, versus the limit of 40 dBA by night for hospital areas). Instead, a normal situation has been ascertained for the remaining pollutants of the study: the concentrations of carbon monoxide (CO), carbon dioxide (CO2) and ozone (O3) were consistently maintained below the limits for health protection during the whole survey, as well as monitoring for sulfur dioxide (SO2) and volatile organic compounds (VOCs). Air concentration of PM10 and Leq values for noise were, in different times, above the reference limits and surely prejudicial to human health, not only for casual users, employees and students, but especially for the most sensitive patients accessing the hospital; the highest average values were found in periods corresponding to hours of greater intensity of traffic, or rather in the morning and late afternoon, decreasing, however, during the night. It supports the hypothesis that the main anthropogenic source for pollution should be found in the excessive road traffic and transport, as well as data of other urban areas confirm.