Session Inactivity and browser reset

I use a simple session like

 

session add simple [HTTP::cookie value mycookie] active 60

 

Then when a request comes in if I do not have the session then i flag it as having a period of inactivity....

 

 

So I can catch the next request and block them from going further. But they want the screen redirected to remove any data that may have been being displayed. Not worried about the cache. These are Kiosks in the warehouse for the workers to check the hours paycheck etc. They will be locked down to where they cannot do much, the worry is that someone will walk off and leave their information on the screen.

 

 

I though about injecting javascript but not sure how that would work.