Documents threshold of discomfort 5 results

Office chairs have often been designed to promote a single 'correct' rather rigid and upright posture, yet it is acknowledged that allowing changes in posture is good ergonomics practice. The present study investigated office worker's preferences for a standard shaped typist's chair (ST) and a prototype multi-posture (PMP) office chair designed to allow its users a variety of sitting positions.The findings suggest that a more aesthetically acceptable PMP chair should be developed, peoples' reasons for preferring a more traditionally designed chair should be explored, and that the effect of postural stability education on personal preconceptions should be examined to obtain an optimal combination of healthy sitting habits, comfort and aesthetic qualities in an office chair.

To help in the design or redesign of workplaces it would be helpful to know in advance the postural stress consequences of a wide range of body postures. This experiment evaluated 168 postures chosen to represent those in the Ovako Working-posture Analysing System (OWAS) using Rated perceived Exertion (RPE) and Body Part Discomfort (BPD) measures. The postures comprised all combinations of three arm postures, four back postures, seven leg postures and two forces (weights of held boxes).

"This cross-sectional study of a group of assembly workers (n=289) tested the hypothesis that affective stress responses mediate the effect of psychosocial work conditions on musculoskeletal complaints (MSCs). Self-reported work demands, control, social support, stress, energy, and MSCs were analysed in hierarchical logistic regression analyses. High work demands were related to a higher risk of shoulder problems. Work demands and social support, but not control, were related to stress; and more musculoskeletal complaints were found in the group with high stress than in the low-stress group. The analyses supported the hypothesis that the effects of work demands on shoulder problems were mediated by the affective stress response, whereas this did not seem to be the case for the effect of social support and control conditions on neck problems. A weaker relation to psychosocial work conditions was shown for back problems than for shoulder and neck problems."

"North American workers usually stand while working, and prolonged standing is associated with discomfort and cardiovascular problems. Since prolonged sitting is also associated with health problems, and standing postures differ as to mobility and access to seating, it is desirable to identify an optimal mix of postures. As a step towards this identification, it is desirable to develop indicators of potential health effects that respond to changes in work requirements. We observed 65 subjects who usually stood at work, in four types of workplaces. Pressure-pain threshold (PPT) recorded on the plantar surface was used as an indicator of discomfort and arterial blood pressure was used as an indicator of cardiovascular effects. PPT after work was significantly lower than that before work. Sitting for even a small part of the day appeared to be protective. The effects of static vs. dynamic work on PPT and arterial blood pressure may differ."

"L'"ipoacusia da rumore" costituisce circa il 54% di tutte le malattie professionali indennizzate dall'INAIL. Questo testo, che deriva dalle lezioni tenute negli ultimi dieci anni presso la Scuola di specializzazione in Medicina dell'Università di Milano, raccoglie nozioni di acustica, indizioni pratiche per procedere alla valutazione del rumore negli ambienti di lavoro, nozioni relative alle caratteristiche e alle modalità di funzionamento degli strumenti, formule per il calcolo del Livello di Esposizione Personale (LEP) come previsto dal DDL 277/1991, principi generali di bonifica ambientale.

Per quanto riguarda l'ipoacusia da rumore, vengono dapprima presi in considerazione aspetti generali quali autonomia e fisiologia dell'apparato uditivo, tecniche di misura dell'udito e principi di diagnostica audiologica, quindi argomenti più specifici: eziologia e patogenesi del trauma acustico, rapporti tra rumore e danno, percorsi diagnostici, prevenzione valutazioni medico-legali.

Corredano il volume le tabelle per il calcolo predittivo dei deficit uditivi di lavoratori esposti al rumore occupazionale (ISO 1999) e valori di riferimento della soglia uditiva attesa di maschi e femmine per anno di età. Una bibliografia aggiornata consente infine al lettore un notevole approfondimento dell'argomento.

Questo libro è uno strumento che, grazie alla ricchezza e alla completezza delle informazioni, mette lo specialista in grado, non solo di fare una corretta diagnosi della malattia, ma anche di valutare e misurare il rumore stesso e di affrontare i numerosi problemi derivanti dalle leggi relative agli ambienti di lavoro e da quelle assicurative sia in campo penale che civile."