Do we have time limitation for DND ??

yes, there is time limitation which will be according to the policies of our seniority

DND limitation should be not more then10hours.

yes there is time limitation as the rooms needs to be serviced

Yes, there is a time limitation for DND rooms. That time will depend on your company's Policies and Procedures. 

yess..We have time limited for the DND Room, in a convenion time..