**8. Conclusions**

In this research we have designed, developed, and evaluated a new tool based on the usage of lighting sensors, which allows users to evaluate the level of illuminance in both working spaces, outside and inside. So, it allows users to know the degree of compliance of UNE standards, allowing its use in the prevention of occupational risks.

The results sugges<sup>t</sup> that the usage of this tool allows users to obtain, with enough accuracy, the value of the illuminance in a working place. In addition, the rules engine implemented offers useful information through recommendations for improvement, helping with decision-making tasks, allowing the decrease in the number of sick leaves caused by bad lighting in the workplace.

The developed system was evaluated by professionals from two points of view: practical and technical. The results offered some feedback and suggestions about the system. The feedback from caregivers showed that the proposed system can streamline and improve the process of risk prevention due to illumination of jobs and workplaces.

The use of a Web server where all the measurements are performed with the application allows us to collect information about the level of compliance with the standard, and to use this information in other future studies about the compliance of regulations among others.

**Acknowledgments:** The authors want to thank the effort and the support that University of Alcalá and University Rey Juan Carlos have offered to the Department of Computer Science of UAH and Business Economics Department of URJC in the "CEI 2017 Intelligent Energy" project. V638.

**Author Contributions:** Ana Castillo-Martinez and Jose-Amelio Medina-Merodio have developed the mobile application used along the experiments and performed the analysis of the results obtained on the different experiments; Jose-Maria Gutierrez-Martinez and Juan Aguado-Delgado have been in charge of the experiments performed, and Carmen de Pablos-Heredero and Salvador Otón have coordinate the work and validated the results.

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