Thirteen Maryland hospitals will participate in an emergency response drill Wednesday to test the region’s ability to handle a mass casualty terrorist attack.

The so-called “Capital Shield” drill, part of a series of exercises conducted by the military and local and state response units, is designed to simulate the transport and treatment of mock victims to area hospitals.

First responders and hospital staff will practice rescues, triage, treatment and decontamination procedures, and transporting people by helicopter and ambulance, organizers said.

The exercise will be held from 8:30 a.m. to 2 p.m. Wednesday, starting at Montgomery County Fire Rescue Training Academy on Great Seneca Highway in Rockville.

Area residents can expect additional helicopter traffic. People may see mock victims dressed up to look as if they have been severely injured and hospital staff in protective gear simulating the decontamination process.

Organizers said that the exercise will not affect how quickly real patients are seen at local hospitals.

Montgomery, Prince George’s, Calvert, St. Mary’s, and Charles County hospitals as well as Montgomery and Prince George’s County EMS will be testing their response.

The University of Maryland’s Center for Health and Homeland Security will evaluate the drill.