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The estimation of the transmissibility of antivibration gloves requires the use of handheld adaptors for holding the accelerometer and assure that it is correctly positioned at the palm level of the hand. The marketplace proposes only few adaptors, specially made for hand-arm vibration measures, so researchers often had to make their proper homemade adaptors to performing their experiments on the gloves' transmissibility. A way to easily build hard-plastic adaptors is given by the possibility to use 3D printers, but in the literature, there is a lack of information about their properties. This paper investigates the properties of 3-D printed adaptors, confronting different materials among the most used (PLA, ABS, and Nylon), and evaluates possible changes of their performance at different infill densities. Results show that 3-D printed adaptors can be a valid alternative to those present on the market. At middle-low frequencies (10 Hz-400 Hz) their transmissibility values are inside the range ± 0.05. No significant differences were found between the transmissibility of those printed at 50% or 100% of infill, especially when the acceleration is Wh weighted. It has been also experimented a simple solution that aims to reduce possible misalignments of the adaptor when inserted inside the glove. Two external landmarks were designed in order to have a visual check of the position of the adaptor. The first, coming out from the glove through a little slit, was made for checking about the rotation on the Y-Z plane, while the second, parallel to the wrist, was made for checking rotation on the X-Z plane. The statistical analysis, among 30 measures performed by three operators holding the instrumented handle of a mono-axial shaker, supports the idea that the first landmark can help to achieve a better alignment of the adaptor, limiting its rotation along the Y-Z plane. Lesser evidence resulted on the reduction of the misalignment on the X-Z plane, due to the use of the second landmark. A possible reason is the small thickness of the ordinary leather glove used in the tests, which produces too little misalignments angles for being checked by the adaptor's landmark. Some further tests can be carried out using anti-vibration gloves, generally made of thicker and softer materials.

The internationally recognized procedure ISO 354:2003 for measuring sound absorption coefficients under diffuse field conditions is now under revision. The main reason for this revision is the limited reproducibility of absorption coefficients measured in different laboratories that may have significant implications spanning from room acoustic design to material selection. A network of Italian laboratories have come together to carry out an Inter-Laboratory Test (ILT) to assess and compare the measurement uncertainties resulting from the application of the current version of ISO 354:2003 and of the new ISO/CD 354:2019. After detailing the methodological aspects, the paper presents the results of the measurements, discussing the compliance of the laboratories to the standard requirements and new qualification tests, and, more importantly, providing a quantitative estimation of their effects on measurement uncertainty and accuracy. (C) 2020 Elsevier Ltd. All rights reserved.

Occupational diseases linked to noise risk are still one of the most important employment problems, particularly in the quarry activities. Many negative effects on human health can arise after long exposure to noise in an occupational context. To protect workers' health and prevent hearing problems, employers must provide to workers with hearing protection equipment. In recent years, however, there have been many problems with the use of hearing protection devices. These have a highly mitigating effect but can isolate the user from the outside environment, as transit of a vehicle or movement of a digger. This aspect must be treated with care because the workers cannot hear the sound of a hazard alarm or communication with other people during daily activities, for example in a quarry site. Generally, these types of hearing protection devices are made using an exclusively passive mechanism system, which is the related to the insertion loss. For this reason, an experimental campaign was carried out for the purpose of analyze the characteristics of devices equipped with electronic sound amplification systems. The tests were carried out in a sound laboratory with a special noise source on a human mannequin in order to replicate as much as possible the real noise exposure. The aim of the tests was to analyze the behavior of hearing protectors under different noise levels in order to comprehend the degree of effective protection for workers. The signal analysis was carried out in the third octave band, calculating the different noise levels in the frequency spectrum for the different noise levels of the source. The data obtained show that electronically controlled protection devices allow sound to be heard from the environment but at the same time protect against dangerous high noise levels. The results obtained demonstrate the importance of the performance of these devices compared to those based on insertion loss.

Il presente manuale sulla Certificazione acustica e vibratoria delle macchine, oltre ad un quadro generale legislativo e normativo e alle procedure per la certificazione acustica e vibratoria delle macchine, è stato effettuato un approfondito censimento delle norme UNI, EN, ISO, oltre alla manualistica e ad altre norme internazionali utilizzate nella prassi consolidata. Il manuale affronta gli aspetti relativi alla certificazione delle macchine, non il rischio di esposizione e relativi obblighi del datore di lavoro, per il quale si rimanda alla manualistica presente nel sito Inail e nel Portale agenti fisici (PAF). Il manuale si pone l'obiettivo di fornire una immediata operatività agli addetti aziendali e industriali e ai loro consulenti. Infatti, la possibilità di consultare le schede tecniche relative alle norme censite fornisce una visione di insieme di tutte le norme applicabili, suddivise per settore (rumore e vibrazioni). Inoltre, il database, una volta implementato su supporto informatico, permetterà di eseguire ricerche specifiche per le principali tipologie di macchine e attrezzature, permettendo di individuare le peculiarità e le differenze e indirizzare l'utente verso le scelte più appropriate per ciascuna tipologia di macchina. Il manuale costituisce uno degli strumenti operativi per la riduzione dei rischi previsti dal comma 3ter del d.lgs. 81/2008.

Dosimetric measurements carried out on basketball referees have shown that whistles not only generate very high peak sound pressure levels, but also play a relevant role in determining the overall exposure to noise of the exposed subjects. Because of the peculiar geometry determined by the mutual positions of the whistle, the microphone, and the ear, experimental data cannot be directly compared with existing occupational noise exposure and/or action limits. In this article, an original methodology, which allows experimental results to be reliably compared with the aforementioned limits, is presented. The methodology is based on the use of two correction factors to compensate the effects of the position of the dosimeter microphone (fR) and of the sound source (fS). Correction factors were calculated by means of laboratory measurements for two models of whistles (Fox 40 Classic and Fox 40 Sonik) and for two head orientations (frontal and oblique).Results sho w that for peak sound pressure levels the values of fR and fS, are in the range -8.3 to -4.6 dB and -6.0 to -1.7 dB, respectively. If one considers the Sound Exposure Levels (SEL) of whistle events, the same correction factors are in the range of -8.9 to -5.3 dB and -5.4 to -1.5 dB, respectively. The application of these correction factors shows that the corrected weekly noise exposure level for referees is 80.6 dB(A), which is slightly in excess of the lower action limit of the 2003/10/EC directive, and a few dB below the Recommended Exposure Limit (REL) proposed by the National Institute for Occupational Safety and Health (NIOSH). The corrected largest peak sound pressure level is 134.7 dB(C) which is comparable to the lower action limit of the 2003/10/EC directive, but again substantially lower than the ceiling limit of 140 dB(A) set by NIOSH.

The work operations in the quarry activities are the source of many physical agents such as dust and vibrations but especially noise. This last can have relevant negative effects they cause serious problems for the worker’s health. In order to prevent the hearing loss, the employer must provide to the workers the HPD (Hearing Protection Devices). They are inserted inside the ear following a specific procedure to ensure the maximum protection by the noise. For this reason, the use training represents an essential aspect. Also the material, which the device is made of, can influence strongly the actual noise attenuation. The study is based on tests with different HPD, some made of polyurethane and others by silicone. Two experimental campaigns were carried out under different conditions with the same measurement methodology. The results highlight the importance of the methodology used in the test and the relevant role of the use training.

Le vibrazioni sui trattori possono costituire un rischio per la salute degli operatori. L'efficacia di diversi sistemi di controllo delle vibrazioni riguardanti le sospensioni, i sedili e gli pneumatici è stata valutata su un trattore durante l'aratura, la traslazione su terreno non lavorato e la traslazione su strada asfaltata a tre velocità.

Introduction Literature data show that teachers are exposed to increased risk for diseases of the phonatory apparatus. This circumstance is explained by the high phonatory load of teaching and by classroom noise. As passive acoustic requirements of the school buildings are often not respected, the intelligibility inside the classrooms is poor, increasing the teacher’s voice loudness. This work is aimed at studying relations between long reverberation times, high noise levels and vocal effort. Methods Phonatory effort was evaluated in three school complexes, on a sample of nursery (6 subjects), primary (9), junior high (2) and high (8) school teachers. The classrooms were classified as acoustically treated or not. Speech intelligibility was quantified by the speech transmission index (STI). Phonatory doses were correlated to noise exposure levels and to classroom acoustics. The phonatory effort was evaluated with the Ambulatory Phonation Monitor (Kaypentax). Result Vocal effort was associated to school degree, showing an increasing at the primary school where the pupils are noisier. A significant association was found between the sound level evaluated 15 cm from the speaker’s mouth and the noise level (coefficient=1.45, p value=0.016). Multivariate linear regression models explained the sound pressure level emitted by the speaker (SPL) by phonation percentage and reverberation time. Average reverberation times at 1 kHz were 0.8 and 2.3 s, while average STI, evaluated by a theoretical model, were approximately 0.6 (sufficient) and 0.4 (poor), in treated and untreated classrooms, respectively. In untreated classrooms the SPL was on average 30% higher (p=0.041). Discussion The high phonatory load of teaching is significantly worsened by the classroom inadequate acoustic parameters. Long reverberation times and, consequently, poor speech intelligibility, high noise levels and vocal effort are significantly related. Improved acoustic design of the classrooms would reduce the risk for vocal apparatus pathologies.

The Italian vibration database is presented. It is hosted by a web server at the National Institute of Occupational Prevention and Safety (ISPESL) in Rome, Italy (http: / /www.ispesl.it/vibrationdatabase). It supports in risk assessment employers who have to comply with Legislative Decree 187/05, now replaced by Legislative Decree 81/08, which transposes into law Vibration Directive 2002/44/EC. The database currently contains measurements and EC-declared values from over 980 hand-held power tools (such as pneumatic and electric hammers, chainsaws, grinders, drills, sanders and saws) and from over 420 vehicles (such as buses, forklifts and wheel tractors). The database is continuously updated as soon as new experimental and declared data are acquired.

Objectives: To investigate the prevalence of vascular, neurological and musculoskeletal disorders of the upper limb in a group of female workers performing either mechanical or hand sanding in the furniture industry (n=100) and in a control group of female office workers (n=100). A further aim was to study the possible adverse effects of exposure to a combination of vibration and ergonomic risk factors in female workers. Methods: All female workers underwent a medical interview and a complete physical investigation. The clinical diagnoses of Raynaud’s phenomenon and carpal tunnel syndrome (CTS) were made according to international consensus criteria. Hand-transmitted vibration from orbital sanders was measured according to International Organization for Standardization (ISO) recommendations. Daily vibration exposure was assessed in terms of 8-h energy-equivalent frequency-weighted acceleration [A(8)] according to the European Directive on physical agents. Ergonomic load on the upper limbs was estimated by means of strain index methodology. Results: There was no significant difference in the prevalence of Raynaud’s phenomenon between the furniture workers (4%) and the controls (8%). The prevalence of CTS, peripheral sensorineural disturbances (after exclusion of CTS cases) and upper-limb musculoskeletal complaints was significantly greater in the furniture workers than in the controls. CTS was clinically diagnosed in 19% of the furniture workers and 8% of the controls. A log-binomial regression analysis showed that the occurrence of soft-tissue disorders of the upper limb increased significantly with the increase of both daily vibration exposure and the strain index score. It was estimated that the risk for CTS increased by a factor of 1.30 (95% CI 1.11–1.53) for each unit of increase in A(8) (ms−2), and by 1.09 (95% CI 1.02–1.15) for each unit of increase in the strain index score. Conclusions: Even though the cross-sectional design of this epidemiological study does not allow aetiological considerations, our findings suggest a significant association between occupational use of vibratory tools and soft-tissue disorders in the upper limbs of female workers. Quantitative estimation of vibration exposure and ergonomic stress showed that these physical risk factors seem to contribute in a multiplicative way to the occurrence of chronic nerve and musculoskeletal disorders in female workers operating hand-held vibrating tools in the furniture industry.

This article presents the new Italian database of physical agents, which is available at http://www.portaleagentifisici.it. It supports in risk assessment employers who have to comply with Italy's Legislative Decree 81/2008 (transposing into law European Union Directives 2003/10/EC, 2002/44/EC, 2004/40/EC and 2006/25/EC). The database currently contains measurements and declared European Community (EC) values from over 2540 machines; in particular, the database hosts data on mechanical vibration from over 1430 hand-held power tools (e.g., pneumatic and electric hammers, chainsaws, grinders, drills, sanders and saws) and from over 1020 whole-body machines (e.g., buses, fork lifts and wheel tractors). The database is continuously updated as soon as new experimental and declared data are acquired.

The present research concerns the noise analysis of five vessels during navigation and fishing activities. In locations where staff operates, sound levels (produced substantially by the engine) were close to 90 dB(A); within the rest areas the noise is also quite significant. On the basis of working time, exposure levels ranged between 80 and 90 dB(A). In order to identify interventions able to reduce the risk, reverberation times, sound insulation of the different areas and the vibrations produced by the engine were measured on the same vessels docked in port. Noise level reduction as a result of sound absorptive treatments were estimated using an analytical model.

In last years, several research teams pointed their attention on the application of active noise control systems (ANC) inside the cabs of agricultural tractor, with the purpose of reducing the driver exposition to noise, that is only partially controlled by the frame of the cab. This paper reports the results of a first experience that aimed at verifying the applicability of an ANC on a medium-high power, tracked tractor without cab. The tested tractor was a Fiat Allis 150 A, equipped with rear power take off, used in the execution of deep primary tillage in compact soils. It is a tracked tractor without cab, with maximum power of 108.8 kW at 1840 min–1 of the engine. The ANC consists of a control unit box based on a digital signal processor (DPS), two microphones, two speakers and a power amplifier. The instrumentation used in noise data collecting and processing consisted of a multichannel signal analyzer (Sinus - Soundbook), a ½” microphone capsule and an acoustic calibrator, both Bruel & Kjaer. The study aimed at evaluating the behaviour of the ANC by means of tests carried out under repeatable conditions, characterized by pre-defined engine speed values. Three replications have been made for each engine speed. The sampling time was 30 s. Two series of tests were performed in order to compare the results observed with the ANC on and off. The engine speed adopted in the study ranged from 600 min– 1, up to 2000 min–1 (maximum speed) with steps of 100 min–1. The ANC proved to be effective in the interval of speed between 1400 and 1700 min–1, where the samplings have been intensified, adopting steps of 50 min–1. In such an interval, the attenuation observed with the ANC system on appeared evident both as weighed A sound pressure level (from 1.29 up to 2.46 dB(A)) and linear (from 4.54 up to 8.53 dB). The best performance has been observed at the engine speed of 1550 min–1, with attenuations, respectively of 2.46 dB(A) and 7.67 dB. Outside of the engine speed interval 1400 - 1700 min–1, the attenuations always resulted lower than 1 dB(A) for the weighed A sound pressure level and between 0.66 and 7.72 dB.

The article describes the ESCA microscopy beamline dedicated to high spatial resolution quantitative and qualitative analysis on surfaces and interfaces. The scanning microscope is constructed to work both in transmission and photoemission within the photon energy range from 200 to 1200 eV with a spatial resolution of ∼0.1 μm. A Fresnel zone plate demagnifies the photon beam to submicrometer dimensions with 109–1010 photons/s in the focus spot. A photodiode and a hemispherical electron energy analyzer are used as detectors for recording the transmitted x‐rays and emitted photoelectrons, respectively. The operation modes in photoemission give the opportunity to obtain conventional energy distribution curve spectra from a microspot or a two‐dimensional micrograph of the spatial distribution and local concentration of a selected element as the sample is mechanically scanned. For conductive specimen topography measurements of a selected surface area probed by SPEM are possible using a scanning tunnelling microscope. The first test images of a zone plate and an e‐beam written specimen with 1 μm2 Au squares on Si have shown a spatial resolution better than 0.2 μm.

Electro-medical equipment is widely used in order to treat bony and muscular disorders and some neurological disease in rehabilitation. However, the scientific evidence regarding the safety and efficacy of this equipment is meagre and contradictory. We have studied the subject, taking into account current regulations for the management and use of this electro-medical equipment. Following the criteria for Evidence Based Medicine, we have analysed the international literature so as to evaluate the evidence for physical energy in different clinical applications. Because the vast quantity of publications dealing with this material, priority was given to peer-reviewed articles and randomised trials. The publications were divided into categories according to disorder, so as to illustrate how some may provide positive proof whereas others require further study.

School gymnasia and swimming pools are generally environments affected by poor acoustic conditions due to absence of sound absorbing materials, noisy sport activities, presence of many students at the same time and intensive use of blowing whistles to enforce the communication. The consequence is that physical education teachers can not only show long term stress but they can also be exposed to noise risk to noise-induced hearing loss. Investigation has shown that the problem is quite large; as many as 20�25% of physical education teachers can be affected by a noise exposure higher than acceptable limits. It is then necessary to analyze in detail all factors that can influence the noise in these special school environments in order to develop simple acoustical guidelines useful for school officials for stress management and hearing conservation programs.

Il rischio uditivo cui sono esposti gli operatori telefonici è stato finora scarsamente considerato. In questo lavoro si indicano la strumentazione, gli studi e le prove preliminari condotte per la valutazione del rischio per i suddetti lavoratori.

Il rischio uditivo cui sono esposti gli operatori telefonici è stato finora scarsamente considerato. In questo lavoro si riportano i risultati di diverse indagini sperimentali condotte per la stima dell'esposizione di questi lavoratori.

Il numero di operatori telefonici è orami molto rilevante. Sfortunatamente è stato finora poco considerato il rischio uditivo cui detti lavoratori sono esposti. Questo lavoro vuole introdurre tale problematiche alla luce delle tante lamentele arrivate dai singoli operatori.

Twelve seated male subjects were exposed to 15 vibration conditions to investigate the nature and mechanisms of the non-linearity in biomechanical response. Subjects were exposed to three groups of stimuli: Group A comprised three repeats of random vertical vibration at 0.5, 1.0 and 1.5 ms(-2) r.m.s. with subjects sitting in a relaxed upright posture. Group B used the same vibration stimuli as Group A, but with subjects sitting in a 'tense' posture. Group C used vibration where the vibration spectrum was dominated by either low-frequency motion (2-7 Hz), high-frequency motion (7-20 Hz) or a 1.0 ms(-2) r.m.s. sinusoid at the frequency of the second peak in apparent mass (about 10-14 Hz) added to 0.5 ms(-2) r.m.s. random vibration. In the relaxed posture, frequencies of the primary peak in apparent mass decreased with increased vibration magnitude. In the tense posture, the extent of the non-linearity was reduced. For the low-frequency dominated stimulus, the primary peak frequency was lower than that for the high-frequency dominated stimulus indicating that the frequency of the primary peak in the apparent mass is dominated by the magnitude of the vibration encompassing the peak. Cross-axis transfer functions showed peaks of about 15-20% and 5% of the magnitudes of the peaks in the apparent mass for x- and y-direction transfer functions, respectively, in the relaxed posture. In the tense posture, cross-axis transfer functions reduced in magnitude with increased vibration, likely indicating a reduced fore-aft pitching of the body with increased tension, supporting the hypothesis that pitching contributes to the non-linearity in apparent mass.

The growth of the GaP(110)/Cu and GaP(110)/Ag interfaces were investigated via Auger and photoemission spectroscopy. Strong chemical reactivity was found upon depositing Cu onto the GaP substrate. The analysis of the P L2,3VV lineshape revealed the formation of a Cu-phosphide like product while the Ga 2p photoemission line gave evidence of segregation of free Ga atoms. On the other hand, very weak chemical interaction between Ag and GaP is found, limited to the first stage of adsorption and subsequently followed by Ag clustering.

The initial phases of the oxidation of the GaP(1 1 0) cleaved surface have been studied, by photoemission with synchrotron radiation. A first stage in which an increase in band bending occurs and a second stage in which complete saturation of dangling bonds occurs are distinguished. This result accounts for previous surface reflectance data on the same surface. The processes of band bending variation and dangling bond saturation with oxygen exposure are very similar in GaP(1 1 0) and GaAs(1 1 0).

We have performed photoelectron spectroscopy of the clean GaP(110) surface, obtained by cleaving n-type specimens. The results show that Fermi-level stabilization occurs in a wide range of positions. In some cases nearly flat bands were obtained. The surface Fermi-level position in n-type GaP(110) is then due to extrinsic surface states, probably cleavage defects, as in the case of p-type samples. The density of these extrinsic states depends upon the quality of the cleave. Previously the Fermi-level pinning in n-type GaP(110) surfaces instead was attributed to (empty) intrinsic surface states located at 1.6+/-0.1 eV above the valence band. GaP(110) was considered an exception among III-V compounds, since in general atomic relaxation removes intrinsic surface states from the fundamental gap. The present results set a lower bound for the energetic position of the empty surface states slightly below the bottom of the conduction band. Therefore GaP(110) exhibits a gap practically free from intrinsic surface states, like the other III-V compounds so far investigated. We have also performed a spectroscopic study of the empty (intrinsic) surface states on the same surface by measuring the absorption edge of the P 2p core level. The result shows that the wave functions of the empty dangling-bond states, mainly cationic in origin, have a sizable localization on the anion site as well.

This report presents the project for the development of a combined facility consisting of a high spatial resolution soft x-ray scanning photoelectron microscope (SPEM) and a scanning tunnelling microscope (STM) that is going to be built in an ultrahigh vacuum (UHV) station on one of the undulator beam lines at ELETTRA, Trieste. The photon microprobe for SPEM will be generated using a zone plate diffraction optic. A special design of a spherical grating monochromator will provide the source for illuminating the zone plate. The emitted photoelectrons will be detected and analysed using a high-energy resolution hemispherical analyser with a large acceptance angle. The performance of the SPEM is projected to be as follows: (1) a photon spot size on the sample of ∼50 × 50 nm2; (2) a tunable photon energy range of 200–800 eV, with an energy resolving power of 3000 at the carbon K-edge; (3) a photon flux in the spot that is > 109 photons s−1 (0.1% body wt.)−1. The projected performance of the STM instrument ensures a lateral resolution better than 2 A. The combination of SPEM and STM techniques will enable chemical and structural mapping within the same microscopic areas of the sample surface. Descriptions of the main beam line components together with some examples of possible applications of this unique tool are included in the paper.

We have performed a photoemission study of the Schottky barrier obtained by depositing Ag onto UHV cleaved GaP(110) at room temperature. The barrier appears to be fully developed at a coverage of ∼2 monolayers and its height is 1.1 eV. This figure is to be compared with higher (lower) values obtained with metals having a larger (smaller) work function than Ag, for example Cu and Au (In and Al) deposited onto the same surface. The result corroborates the idea that the metal–GaP(110) interface is a good example of the Schottky limit in metal–semiconductor junctions. The effective work function model proposed by Woodall and Freeouf provides the best interpretation of the Schottky barrier height in this interface.