Slow-motion analysis of the video showed that Joy was electrocuted by a malfunction on stage.
The incident occured during the March 13 episode of live music show Inkigayo
The 12-member girl group have released a massive amount of teasers and information ahead of their first album release.
The SHINee member's first full-length album will contain 10 tracks.
They were performing 'A' when a sudden burst of fireworks at the front of the stage nearly Youngjae in the face.