Text 911 services have launched in four metro Atlanta cities.

Residents in Sandy Springs, Johns Creek, Dunwoody and Brookhaven will now be able to send text messages to the emergency line, in addition to calling.

The service is meant for people who are deaf or hard of hearing, who have a speech disability, or who are in a position where they cannot safely call 911 in an emergency.

The system cannot receive pictures or video, and the deputy director of operations for the Chattahoochee River Authority system said calling 911 is still preferable to text. Over the phone, operators are able to ask vital questions more quickly, he said in a statement.

“If a caller has a hearing or speech impediment or is in a dangerous situation where placing a verbal call could enhance that risk, Text to 9-1-1 can be a lifesaving option,” Stephen Pierce, the deputy director of operations, said.

Callers who text 911 will get a message back that says, “If it is safe to do so, please call 9-1-1.”

Individuals texting 911 will be asked to type in an address or street intersection so they can be found.

There is no additional cost to the cities for the text function.