Here is a more detailed outline of hospital status used in the commonwealth for ED status by EMS providers.
Condition Green: The Emergency Department is open with no restrictions
Condition Yellow: The Emergency Department is busy but not overwhelmed. Patients presenting to the Emergency Department via EMS may experience significant delays in treatment due to the current volume and/or acuity of patients already in the Emergency Department. EMS personnel should inform the patient of this situation and consider transporting the patient to another facility if the patient consents.
This condition automatically terminates in 4 hours unless renewed.
Condition Red: All of the usually available resources in the Emergency Department are overwhelmed such that receipt of additional patients will result in the inability to care for them safely. Patients may not be brought to the Emergency Department unless EMS personnel perceive the patient to be suffering from an immediately life-threatening illness or injury.
This condition automatically terminates in 2 hours unless renewed.
Condition Black: A hospital/facility may be reported in "Condition Black" when an emergency situation or catastrophic event exists that renders the entire facility as being unsafe. Examples of such events include but are not limited to: Fire, explosion, bomb threat, gun fire, nuclear/biological/chemical incidents, etc.
No patients shall be transported to facilities that are reported as in "CONDITION BLACK"
Source: Hospital Status monitor at EMS.org