Each EMS Regional Council has identified specific geographic areas to monitor hospital yellow alert frequency and duration on a daily basis. These areas consist of the following groupings of 24 hour Emergency departments or special services.
| Region I: |
The 3 hospitals within Allegany and Garrett counties. |
| Region II: |
The 2 hospitals within Frederick and Washington counties. |
| Region IIIa: |
The 16 hospitals within Baltimore county and Baltimore city. |
| Region IIIb: |
The 6 hospitals within Anne Arundel, Carroll, Harford, and Howard counties. |
| Region IV: |
The 7 hospitals within Caroline, Cecil, Dorchester, Kent, Queen Anne's, Somerset,Talbot, Wicomico, and Worcester counties. |
| Region Va: |
The 9 hospitals within Western Washington D.C. and Montgomery county. |
| Region Vb: |
The 10 hospitals within Eastern Washington D.C. and Prince George's county. |
| Region Vc: |
The 3 hospitals within Calvert, Charles, and St. Mary's counties. |
The graphs for Region III and V are provided to show the daily yellow alert demand based on the following formula:
Total Number of daily minutes on yellow alert
Thresholds for regional daily percent and the consecutive days at or above that level have been predetermined for phases of voluntary and/or mandatory compliance actions. Available historical trends have been included for reference.