In which the ductwork leaves the compartment from which it serves (proven in blue) it have to preserve integrity and insulation fire scores for the same time frame as the compartment through which it passes. CIBSE welcomes new transitional arrangements for setting up Manage inspectors registration in England Even following https://riverjbqer.tribunablog.com/how-cibse-can-save-you-time-stress-and-money-43420111