To accurately identify occupational health and safety hazards in different industries with distinct characteristics, a comprehensive occupational ergonomics assessment scale was developed by integrating the Rapid Upper Limb Assessment (RULA) evaluation framework, the Rapid Entire Body Assessment (REBA) and the Ovako Working Posture Analysing System (OWAS) . Between May 2023 and May 2024, based on the proportional reasoning method and segmented function method, the algorithm logic of RULA and REBA was aligned, and the evaluation rules for the revision content of the innovation scale were inferred using the method of proportion reasoning. Twenty postures were randomly selected for correlation verification. The results showed that at a significance level of α=0.01, the normalized score of the comprehensive ergonomic assessment scale had a correlation coefficient of =0.845 with RULA and =0.633 with REBA. The behavioral level score of the comprehensive ergonomic assessment scale had a correlation coefficient of =0.911 with RULA and =0.737 with REBA, indicating significant correlations. The innovative comprehensive ergonomic assessment scale has high reliability and can be used for work activities in different workplaces and work contents, promoting the standardization of ergonomic assessment of occupational exposure hazards.