Assessing the Impact of Shift Schedule Change from 12-Hour to 8-Hour Pattern on Prevalence of Health Problems in a Petrochemical Company

After conducting a study on shift work and its related health problems in a petrochemical company and recommending a new shift system، the company changed its shift schedule from 12-hour to 8-hour pattern. After a year of implementing this new system، the present study was carried out to evaluate the effects of this change on health problems of shifting workers. In this cross-sectional study، the subjects consisted of 79 shifting workers of the present study and 74 shift workers from the previous study. Data were collected by an anonymous questionnaire، similar to the one used in the previous study، in which questions on demographic characteristics، health problems and workers’ views about shift pattern change were included. Mean working experience in shift work workers of the present and the previous study were 5. 91 ± 2. 40 and 5. 18 ± 3. 79 years، respectively (P > 0. 05). The results showed that the prevalence of some gastrointestinal and musculoskeletal problems in the present study were statistically and significantly higher than those of the previous study (P < 0. 05); however، the prevalence of some psychological disorders were lower in the present study subjects as compared to the individuals of the previous study (P < 0. 05). The results revealed that from the viewpoint of shift workers، new shift pattern improved quality and quantity of sleep. Furthermore، the findings showed that 97. 5% of the subjects evaluated the new shift schedule to be better than the previous one. Based on the findings، changing the shift pattern from 12-hour to 8-hour system resulted in decreased prevalence of psychological problems، improvement of sleeping quality and improvement of their lives. It is، therefore، concluded that the change implemented in the shift pattern was useful، and most subjects evaluated it to be effective and positive.