Runners in today’s Boston Marathon—including a group of about 90 Harvard students—will help public health officials test a new way of responding to earthquakes and terrorist attacks.

All participants will wear bar-coded bibs, which will allow event organizers to track injuries and hospitalizations, thanks to a grant from the federal Department of Health and Human Services.

Aleksei Boiko ’06 will be among the Harvard students running the marathon today. “I’m extremely concerned about injury, as I’m already nursing one,” he said. Though he appreciates the new system, he said he still plans to carry a cell phone.

Eric T. Hoke ’06, who will also run in today’s race, said he was particularly happy about the bar codes. Two years ago, he lost consciousness just as he crossed the finish line and was treated at a medical tent for dehydration and heat stroke. “I’m happy it’s there for my safety,” he said.

More than 22,500 athletes are expected to run the 26.2 mile race today. Every year medical personnel receive upwards of 800 runners who require attention; when temperatures spike, that number can exceed 1,700, according to an assistant commissioner of the state Department of Public Health, Nancy Ridley.

Organizers will use hand-held scanners to record the name, age, gender, and medical status of every injured athlete. The information will then be available to event organizers and local hospitals. Family and friends will be able to inquire about a runner’s status at a kiosk near the finish line.

The main purpose of such a system is to ensure that no runner is lost, but public health officials say they hope to use the Boston Marathon as a test of the patient tracking system. Officials hope to implement a similar system to respond to disaster situations that flood hospitals with casualties, according to Ridley.

Hurricane Katrina, for example, created chaos in New Orleans when government officials and families had no way to access information about patients being treated in area hospitals and makeshift medical tents. Giving all incoming patients a bar-coded bracelet would alleviate the chaos by centralizing patient data, Ridley said.

—Materials from the Associated Press were used in the reporting of this article.