[Can an openable window be fitted to an internal wall?]

I thought as much, thanks. Even if a fire proof openable window could be found, how could it be guaranteed that the window would be closed in the event of a fire, it couldn't. 

Cost would also definitely be an issue with this! 

[Can an openable window be fitted to an internal wall?]

I have an office in a nursing home that has no window, but all the four walls are internal so there is no option of having a window that opens outside. 

To add some natural light and airflow a window has been requested, but as this would open into another area of the home (corridor/escape route) how could an openable window be safe? 

Surely only a non openable fire resistant window can be fitted?