## 5 Conclusions  
The following conclusions can be drawn from the present study:  
1. In general, occupants have a moderate or low access in the control of their indoor working environment. They have rated with a moderate control perception the lighting and shading from the sun parameters. Noise was the worst control parameter, while temperature and ventilation control were rated in the low control scale. Among the five control parameters, there was a significant group of occupants who were not able to control their environment at all. Nearly all occupants have no or low control on noise. Half of the occupants declared no or low control on ventilation and temperature conditions. Almost one-third of them remarked that they do not have satisfactory levels of control for lighting and shading from sun conditions. It is noteworthy that as the occupancy within the offices increases, the degree of personal control becomes lower.
2. Occupants with a higher level of personal control were reported to be more productive within their working environment. Moreover, occupants who declared high degrees of personal control reported higher levels of IEQ satisfaction.
3. Some significant correlations were found between the available controls within the building and the perceived control. The availability of operable windows had a higher impact on the occupants' control perception over temperature, ventilation, light and noise than floor area or occupancy. Perceived control over temperature differed significantly with the different types of solar devices.
4. Occupants' perceived control is related to psychological aspects. General building characteristics, such as floor number and floor area, office type, operable windows, etc., which help occupants feel freedom were positively associated with the perceived control. ERI remains a significant parameter of the controlling perception in office environments.
5. Concerning the impact of perceived control on perceived comfort, the results of the present study are in general agreement with the literature. More specifically: * The perceived combined control over all studied parameters is positive on the overall comfort * The combined control over all parameters seems to have a stronger effect on overall comfort than the single controls * Temperature variation seems to be more related to the combined control of temperature and shading from the sun control * Combined control perception over temperature, ventilation and shading positively affects the occupants and gives them the feeling of fresher air and an overall satisfaction with air quality * Noise from the buildings systems seems to be more affected by the combined control perception of all parameters rather than single controls * The combined perceived control of all parameters was found to affect the occupants' privacy, office layout and decoration satisfaction more
6. Regarding reported health symptoms, office occupants with a higher degree of personal controls reported less building-related health symptoms.  
Conceptualization, I.S., D.S., C.M. and J.B.; data curation, I.S.; formal analysis, I.S.; funding acquisition, J.B.; investigation, I.S., D.S., C.M., Y.d.K., S.F., A.S., A.C., T.S. and V.M.; methodology, I.S., C.M., Y.d.K. and J.B.; project administration, J.B.; resources, K.K.; supervision, D.S. and J.B.; visualization, I.S.; writing-original draft, I.S.; writing-review & editing, D.S., C.M., Y.d.K., S.F., A.S., A.C., T.S., V.M., E.d.O.F., K.K., P.C. and J.B.  
This research was funded by the European Union 7 th 427 Framework, grant number Agreement 265267 under Theme: ENV.2010.1.2.2-1.  
**Acknowledgments:** This work was supported by the project \"OFFICAIR\" (On the Reduction of Health Effects from Combined Exposure to Indoor Air Pollutants in Modern Offices).  
**Conflicts of Interest:** The authors declare no conflict of interest.