A member of the Dash 8's pushback crew received a minor injury when he attempted to detach the tow bar during engine start when the hydraulically energized nose gear doors struck him in the shoulder. Lack of proper training was cited as a contributing factor.

Narrative

Our pushback driver; who was wearing a headset; shouted something indistinguishable which prompted me to look at him; and then look around outside where I saw another ground crewmember walk away from the aircraft; hunched over and clutching his shoulder. I told the Captain to abort starting the right engine and we queried the tow driver who informed us the ground crewmember was hit by the nose gear door as the engine started. Neither of the ground crew reported the incident and the affected crewmember appeared to be OK after a couple minutes.There was moderate rain and it was still dark which made it difficult for us to see that the ground crewmember ducked under the aircraft nose as soon as we started engine 2. After speaking with the Station Operations Manager it wasn't clear whether the ground crewman attended the appropriate training on the Q400 landing gear hydraulic system operations during engine start.There MUST be some sort of verification that station crews have been trained as we are dealing with people's lives and livelihoods. The company should mandate that each station has a list of ground crewmembers who have completed the training and ensure no crewmembers are working around the aircraft unless they have completed that training. In addition; the phraseology used by the tow driver to alert us of the incident was neither distinguishable nor standardized. This situation must be addressed via additional training to ensure the flight crew can take appropriate and immediate action based on clear communication by ground crews.