It is advantageous to handle certain conditions when equipment (or equipment components) is taken out-of-service or shutdown for service or maintenance. Equipment service flags may be used to indicate that an individual variable will no longer be propagated as the associated equipment has been taken out of line for service. When multiple variables feed another system or component downstream, those variables may be placed in an equipment service set and that set may be associated with an indicator that indicates that the group of variables in the equipment service set is unavailable. A visual indicator as to which variables have been made unavailable for propagation may be displayed to a user. Once the equipment or system is brought back online or is taken out of equipment service mode, the appropriate flags and equipment service set are reset and associated variables are once again propagated downstream.