Conversion formula limit time

Content

Hello experts.

I need a Conversion Formula (Global absence type duration) that actually limits the duration.
The schedule is default for the whole company from 6 to  22 hours. 
When user launches his day and doesn't look carefully it gives us 16 hours instead of 9 or 7 he actually worked based on his assignemnt working hours time.

Could anyone help wich paaremters may I use that might solve this issue? or if there is any other way to do it besides fast formula

Thanks


 

Version

20D