Background: The assessment procedure of occupational disease no. 2108 (lumbar spine disease) is usually based on a detailed retrospective exposure analysis. The Mainz-Dortmund Dose Model (MDD), specifically developed for this purpose, provides a standardized method to estimate the lumbar disc-compressive forces based on six equations for lifting and carrying of objects and one for extremely trunk-flexed postures. As the MDD was not among the best dose models in the German Spine Study (EPILIFT), within the framework of a reanalysis of that study (EPILIFT Exposure Criteria Study or EPILIFT 2), it was attempted to modify the equations and develop an improved instrument suitable for application in the procedures related to occupational disease no. 2108. Materials and methods: The equations were deduced based on the EPILIFT study, in which the occupational exposure of approximately 1,200 participants was assessed through the use of expert interviews and subsequent individual biomechanical modeling of the lumbar disc-compressive forces. The data set included approximately 1,900 different load combinations of lifting, lowering, transferring, holding, and carrying sequences that allowed for the deduction of formulas to estimate lumbar disc-compressive forces by using linear regression. In order to create a praxis-orientated set of equations, the combinations had to be reduced by representative selections and meaningful grouping. To validate the equation-based compression force estimation, a method comparison was performed for the equation-based exposures and the biomechanically modeled action-specific exposures (via "The Dortmunder" simulation program) for a total of 4,450 work shifts. Results: After assessing several intermediate steps, a final equation set was derived, which consisted of 11 equations for lifting, holding, and carrying tasks in addition to four factors for the description of one-handed, overhead, or asymmetrical load carrying. In the examination of the validity of the relevant exposures for different dose levels, good to acceptable conformity was found for the comparison with calculations based on biomechanical simulation defined as the "reference standard." Conclusions: The key results of the EPILIFT 2 study were adequately reproducible, with the "final" equation set and the 11 equations and four factors for manual load handling appearing to be suitable for practical use. The derived equations can be applied independently of the discussion on the definition of critical values of occupational disease no. 2108.