One of the electricians, a 35-year-old man, suffered second and third degree burns to his body.
He was taken to the Temple University Burn Unit and is currently in stable condition.
The second worker, who is 40 years old, was taken to Presbyterian Hospital, having suffered superficial burns to his face and hand.
Eight PECO customers lost power as a result of the accident.
PECO says both men were wearing appropriate personal protective equipment.
The Occupational Safety and Health Administration was notified of the incident and they have initiated an investigation.
OSHA will have six months to release its findings.
The Public Utility Commission is also investigating the incident.