Virginia is making a change to the information residents can put on their state ID cards, and it could save lives.
As of Tuesday, Virginians can choose to add a blood type indicator to their driver's license.
The small symbol will appear in the upper right-hand corner of Virginia credential cards, near the indicator for organ donors.
It's a small black droplet, with the letters and symbols for whichever blood type is appropriate inside.
We've got the news you need to know to start your day. Sign up for the First & 4Most morning newsletter — delivered to your inbox daily. Sign up here.
The new symbol will help first responders act more quickly in an emergency, the Virginia Department of Motor Vehicles said in a news release.
"The law was intended to aid individuals and first responders when every second counts in an emergency," said DMV Commissioner Gerald Lackey in the release.
"DMV is proud to provide Virginians with options. On your driver's license or ID, you can indicate not only your blood type, but also your willingness to be an organ donor, your veteran status and can even list important medical indicators."
The state bill, now law, was introduced by Sen. George L. Barker, who represents parts of the City of Alexandria, Fairfax County, and Prince William County.
The blood type indicator is optional, and residents can choose to add the symbol to their license or ID card when they renew or replace their credentials online, according to the release.
It's up to those who want to add the blood type indicator to make sure they list the right blood type: There's no proof of blood type required to check off the box on the DMV website.
If you don't know your blood type -- and according to the American Red Cross, many people don't -- there are tests that your doctor can perform with just a few drops of blood to determine whether you have A, B, AB or O antigens, and whether you have positive or negative antigens.
If an accident or tragedy takes place, knowing the victim's blood type is vital to giving them the proper medical care. According to Kaiser Permanente, the combination of antigens in each blood type determines whether someone's immune system will attack donor blood cells.
If you have the same, or compatible, blood type as a donor, a transfusion will help replace lost blood. But if a transfusion uses the wrong blood type, "the antibodies in your plasma will destroy the donor blood cells," Kaiser Permanente says. "This is called a transfusion reaction, and it occurs immediately when incompatible blood is transfused."
Transfusion reactions range from mild to deadly. In an emergency, medical professionals will perform a blood type test to prevent a negative reaction.
But licenses with the driver or passenger's blood type listed out from the start may save precious time -- and even save lives.