The explosion happened around 8:40 a.m. Tuesday at a maintenance shop near Gate D 21, said Reese McCranie, deputy director at Hartsfield-Jackson Atlanta International Airport.
McCranie said there was no fire, but the explosion caused what he described as some "minor property damage."
The explosion briefly shut down power to part of the airport, Atlanta Fire Rescue spokeswoman Janet Ward said.
A partial power outage remained shortly before 10:30 a.m. in some parts of Concourse D, but the fire department had given the "all-clear" and passengers were returning to the concourse, McCranie said.
Delta Air Lines is working with airport officials and others involved to determine the impact to Delta operations, company spokesman Morgan Durrant said.
Though Atlanta is major hub for Delta, the Atlanta-based airline has only a handful of gates in Concourse D.
Durrant said at 10 a.m. Tuesday that Delta didn't know yet whether it would need to delay or cancel any flights, but would take those measures only as a last resort.
Copyright 2013 The Associated Press.