Risk Grade Coverage and Combined Region Coverage


For some analyses, a single combined coverage result is needed for a series of equipment items, e.g. clients who want one coverage results for all compressors in a facility. This can be achieved using risk-grade coverage, as each zone and sub-zone has a risk grade assigned to it.


This 1ooN coverage is calculated by adding up the volume of the combined region seen by one detector divided by the combined volume of all zones and sub-zone assigned to a particular risk grade. The same can be repeated for 2oon and 3ooN with the same denominator. 



In the below example, four sub-zones have been defined around four valves. Each sub-zone is assigned Grade A (indicated by the red arrow). The main zone, Zone 01, has been assigned the Default Grade so that only the four sub-zones make up the Grade A region.


Now when viewing the Coverage Results Table, we can view the Risk Grade Coverage by selecting it from the dropdown menu in the upper right corner of the window (indicated by the blue arrow). This provides the combined coverage of Sub-Zone 01 - Valve, Sub-Zone 02 - Valve, Sub-Zone 03 - Valve, and Sub-Zone 04 - Valve. 


Fire and Gas Mapping Risk Grade Coverage Results  



Note that with Grade A assigned to each of the sub-zones, you may still view individual sub-zone coverage by selecting it from the upper right corner of the coverage results table. 


This process can be used for any combination of created risk grades applied to zones or sub-zones.