**4. Conclusions**

The RULA method has been used in two main areas, "Manufacturing" and "Human health and social work activities". However, it has been found not to be a sector-specific method. It can be applied to workers in any field.

Its use has been increasing over the last 10 years, perhaps indicating it is an effective method which is being tested more and more. This is also coupled with a growing awareness of workers' health and safety. The year that stands out for the number of studies published is 2016 with a total of 32, followed by 2018 with a total of 28.

Countries such as the USA and Iran excel at applying the method and encompassing numerous fields of knowledge. The journal with the most publications is "Work—A Journal of Prevention Assessment & Rehabilitation", with a total of 26. This journal is followed by "Applied Ergonomics" with 16 published studies.

RULA is usually used in combination with other ergonomic methods or tools to provide better and more reliable results. In this way, it is possible to contemplate different risk factors and evaluate numerous body areas. In addition, technological advancement is also appreciated in all sectors, since in many studies the method is combined with the use of sensors, software, virtual reality, etc.

**Author Contributions:** Conceptualisation, M.G.-G., Á.-J.C.-F., J.P.-A., M.D.-P. and J.-A.C.-C.; methodology, M.G.-G., Á.-J.C.-F., J.P.-A., M.D.-P. and J.-A.C.-C.; software, M.G.-G., Á.-J.C.-F., J.P.-A., M.D.-P. and J.-A.C.-C.; validation, M.G.-G., Á.-J.C.-F., J.P.-A., M.D.-P. and J.-A.C.-C.; formal analysis, M.G.-G., Á.-J.C.-F., J.P.-A., M.D.-P. and J.-A.C.-C.; investigation, M.G.-G., Á.-J.C.-F., J.P.-A., M.D.-P. and J.-A.C.-C.; resources, M.G.-G., Á.-J.C.-F., J.P.-A., M.D.-P. and J.-A.C.-C.; data curation, M.G.-G., Á.-J.C.-F., J.P.-A., M.D.-P. and J.-A.C.-C.; writing—original draft preparation, M.G.-G., Á.-J.C.-F., J.P.-A., M.D.-P. and J.-A.C.-C.; writing—review and editing, M.G.-G., Á.-J.C.-F., J.P.-A., M.D.-P. and J.-A.C.-C.; visualisation, M.G.-G., Á.-J.C.-F., J.P.-A., M.D.-P. and J.-A.C.-C.; supervision, M.G.-G., Á.-J.C.-F., J.P.-A., M.D.-P. and J.-A.C.-C.; and project administration, M.G.-G., Á.-J.C.-F., J.P.-A., M.D.-P. and J.-A.C.-C. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Acknowledgments:** We acknowledge Laboratory-Observatory AndalusianWorking Conditions in the Agricultural Sector (LASA; C.G. 401487) and the Research Own Plan of the University of Almería.

**Conflicts of Interest:** The authors declare no conflict of interest.
