Background With the rapid development of China's economy, the working pressure of occupational population has increased rapidly, and the impacts of occupational stress on the physical and mental health of occupational population are becoming an important public health issue. Power supply companies are high risk industries of occupational stress covering many stressors. At present, no systematic research on occupational stress among workers in power supply companies has been reported, especially the impacts of occupational hazardous factors on occupational stress of workers.

Objective The study aims to obtain the current status of occupational stress, explore the correlation between occupational stress and influencing factors, and provide a basis for formulating occupational stress intervention measures through a questionnaire survey of employees of a power supply company in Guangdong.

Methods A cross-sectional study design was adopted and 1 091 employees of a power supply company in Guangdong were selected in May 2019. A general information questionnaire tailored to power supply companies was designed and distributed to collect basic information of the subjects. Occupational stress was assessed by effort-reward imbalance (ERI) indexERI=effort score/(reward score×0.545 4) of ERI scale, and ERI index > 1 was defined as having high occupational stress. Chi-square test was used to compare the differences of occupational stress rate among groups with different individual characteristics, occupational characteristics, lifestyles, and exposures to occupational hazardous factors. Multiple logistic regression was used to analyze the influencing factors of high occupational stress.

Results A total of 1 091 questionnaires were distributed in this survey, and 972 (89.1%) valid questionnaires were returned. The respondents included 859 men (88.4%) and 113 women (11.6%). There were 514 (52.9%) subjects with high occupational stress. The prevalence rate of high occupational stress were higher in men than in women, higher among married employees than among single employees, higher in employees at and over 30 years of age than in those below 30 years, higher in dispatching and maintenance workers than in other types of workers, higher in high-income-level employees than in low-income-level employees, higher in employees with < 6h sleeping time than in those with >7 h, higher in employees with alcohol consumption than in those without, and higher in those exposed to noise, electromagnetic radiation, high temperature and high altitude, and visual display terminal than in those not; these differences were all statistically significant (P < 0.05). The logistic regression analysis results showed that compared with the workers at the age of < 30 years, those at the age of 30-years and 40-years had a higher risk for high occupational stress (OR=2.438, 95% CI:1.507-3.943; OR=2.407, 95% CI:1.472-3.934, respectively); compared with customer service and other types of workers, the maintenance and dispatching workers had a higher risk for high occupational stress (OR=1.841, 95% CI:1.140-2.973; OR=2.417, 95% CI:1.149-5.083, respectively); compared with the employees who slept >7h every day, those who slept < 6h and 6-7h every day had a higher risk for high occupational stress (OR=1.735, 95% CI:1.182-2.547; OR=1.518, 95% CI:1.069-2.115, respectively); compared with those without visual display terminal exposure, the employees with such exposure had a higher risk for high occupational stress (OR=1.419, 95% CI:1.043-1.932).

Conclusion The employees of the selected power supply company generally have a high rate of high occupational stress. Aged above 30 years, at maintenance and dispatch positions, with short sleeping duration, and with exposure to visual display terminal are risk factors of high occupational stress.