The work of Suzhou Hengjiu Optoelectronics requires employees to stand or operate machines for a long time, which is a challenge to employees' physical strength and endurance. Noisy working environment, high or low temperature will increase employees' work fatigue. You also need to work shifts or night shifts. This irregular work and rest will disturb the biological clock of employees, affect the quality of sleep, and then lead to fatigue. Therefore, Suzhou Hengjiu Optoelectronics is tired.