عنوان مقاله [English]
Noise interference with employee’s speech communication is considered as one of the noise pollution effect in any workplace. These interferences can disrupt communication of necessary and vital data between individuals. And as a result can cause anything from a slight irritant to a serious safety hazard involving accident or even fatality. This study was focused on the analysis of the human errors, which occurred as a consequences of noise interference with personnel’s speech communication Isomax Unit of an oil refinery. The personnel’s speech communications was classified in 3 categories : face-to-face communication of Outside Operator (OO) with Head Operator (HO) , communication of Control Room Operator (CRO) with OO by aid of loudspeakers and telecommunication of OO with CRO through the telephones which have been installed in the site.Predictive Human Error Analysis (PHEA) technique was used for identification and analysis of communication errors in the above mentioned communication categories.The most important identified communication according to PHEA sheet , was related to the unintelligible and unclear transmission of message which can be judged mistakenly by the receiving person .
By considering the actual sound pressure level in under study Isomax unit (SPL= 92.7db) and comparing it with the graph of weighted sound level versus distance it was shown that face to face communication error is inevitable . PHEA worksheet results showed that the possibility of speech communication errors in all 3 identified categories is very high .
Therefore it is necessary , apart from considering the noise control measure in the Isomax unit , try to fined some proper solution for improving speech communication by using body language an lip-reading , installation of site telephone in on acoustic booth , use of most sophisticated proper loud speaker , and training of personals on how to be confident about transmission of message and warning statements.
 Miller, J.D ,Effects of Noise on people, in T.D Rassing –Environmental Noise Control Selected Reprints stong brook , NY : American Association of physics teacher 112-147, 1997.