effect of noise on human performance: a clinical trial

Noise is defined as unwanted or meaningless sound that apart from auditory adverse health effects may distract attention from cues that are important for task performance. Human performance is influenced by many job-related factors and workplace conditions including noise level. To study the effect of noise on human performance. The participants included 40 healthy male university students. The experimental design consisted of 3 [sound pressure level] x 3 [noise schedule] x 2 [noise type] factors. To investigate occupational skill performance, some specific test batteries were used: 1] steadiness test, 2] Minnesota manual dexterity test, 3] hand tool dexterity test, and 4] two-arm coordination test. Time duration of test completion was measured as speed response; to determine error response, the time taken during committing an error by participants while performing a task was measured. Speed response obtained from the 4 tests in combined conditions of noise schedule, harmonic index, and sound pressure level was highest for [intermittent, treble, 95 dB], [continuous, treble, 95 dB], [continuous, treble, 85 dB] and [intermittent, treble, 95 dB], respectively. Treble noise was found significant in reducing human performance; also, intermittent noise, especially at high pressure levels, was responsible for worsening environmental conditions during performing a task

Examining the relationship between psychosocial work factors and musculoskeletal discomfort among computer users in Malaysia

With computers rapidly carving a niche in virtually every nook and crevice of today's fast-paced society, musculoskeletal disorders are becoming more prevalent among computer users, which comprise a wide spectrum of the Malaysian population, including office workers. While extant literature depicts extensive research on musculoskeletal disorders in general, the five dimensions of psychosocial work factors [job demands, job contentment, job control, computer-related problems and social interaction] attributed to work-related musculoskeletal disorders have been neglected. This study examines the aforementioned elements in detail, pertaining to their relationship with musculoskeletal disorders, focusing in particular, on 120 office workers at Malaysian public sector organizations, whose jobs require intensive computer usage. Research was conducted between March and July 2009 in public service organizations in Malaysia .This study was conducted via a survey utilizing self-complete questionnaires and diary. The relationship between psychosocial work factors and musculoskeletal discomfort was ascertained through regression analyses, which revealed that some factors were more important than others were. The results indicate a significant relationship among psychosocial work factors and musculoskeletal discomfort among computer users. Several of these factors such as job control, computer-related problem and social interaction of psychosocial work factors are found to be more important than others in musculoskeletal discomfort. With computer usage on the rise among users, the prevalence of musculoskeletal discomfort could lead to unnecessary disabilities, hence, the vital need for greater attention to be given on this aspect in the work place, to alleviate to some extent, potential problems in future

[Control of human errors and comparison of risk levels after correction action with the SHERPA method in a control room of petrochemical industry]

Human errors in many jobs especially in nuclear, military and chemical industries may bring disaster. Supporting this proposal there are many evidence around the world such Chernobyl disaster in 1986, Three Mile Island accident in 1979 and Flixborough explosion in 1974. Therefore, human errors' identification especially in important and complex systems is necessary and thus predicting control methods are unavoidable. Recent research is a case study performed in Zagros Methanol Company in Asalouye [Southern Pars]. The study tools were observation, interview with experts and control room operators, inspecting available technical documents, and completing systematic Human Error Reductive and Predictive Approach [SHERPA] worksheets. Analysis of SHERPA worksheet indicated that,%71.25 were unacceptable errors,%26.75 undesirable,%2acceptable [with modification],%0 acceptable. Predicted risk assessment after modification was%0, unacceptable errors%0, undesirable errors%4.35, acceptable [with modification in future]%58.55, and acceptable errors%37.1. The study showed that the current implemented method can be used through various industries like to chemical and petroleum. Based on the results of the risk level assessment after modifications, once the system weaknesses were refined or controlled we should expect a decrease in the amount of human errors causing disaster

[Assessment of posture in an automotive industry using ISO -11228-3 technique]

Work-related musculoskeletal disorders [WMSDs] of upper limbs [UL] in the last 35 years have become extremely wide spread reaching epidemic levels in all advanced industrialized countries. They are considered the main cause of disability, time off work, and requests for healthcare. For detailed risk assessment, ISO -11228-3 is the preferred method. It is recommended for the specific purposes of ISO -11228-3[2007] because, given the knowledge at the time of publication, it considers all the relevant risk factors, is also applicable to "multitask jobs", and provides criteria - based on extensive epidemiological data - for forecasting the occurrence of UL-WMSD [upper limb work-related musculoskeletal disorders] in exposed working populations. In this method is the ratio between the number of actual technical actions, ATA, carried out during a work shift and the number of reference technical actions, RTA, for each upper limb, specifically determined in the scenario under examination. Results shown in 4 workstations include 35 task in an automotive industry. One of them is red and another's are green. This method is suitable, quickly and very easy to use for assessment of ergonomics situation in work