Narrative:

The captain and pilot monitoring; noted that there was smoke coming from somewhere around the left side of the flight deck and declared smoke in the cockpit. As pilot flying; [I] knocked off my headset and dawned my oxygen mask and noted a bluish color smoke filling the cockpit. This was shortly after we had climbed through FL180. I started a level off and the pilot monitoring ran the immediate action checklist started the QRH and declared an emergency and asked for lower and a heading to the nearest suitable airport for landing. A major airport was about 20 NM away and we were given direct to the airfield for landing. The pilot monitoring dinged the flight attendant to let her know that we were diverting and to prepare the cabin. I then stared a decent at about 4;000 ft per minute. ATC pointed out the airport at about 10 miles away and we turned down wind for landing. On the downwind; I noted that the smoke had dissipated. We decided on the visual to the runway backed up by the localizer. The approach was normal and landing was smooth. After the captain took over after landing we came to a complete stop and the fire crew inspected the aircraft for any visible smoke or fire damage. We then taxied to a gate with a jet bridge and deplaned all passengers. After we were at the gate the fire crew took a look at the battery compartment and noted that there was black soot inside. Total flight time from takeoff to landing was about 21 minutes.we could not establish clear communications with the oxygen masks on. We put on our headsets over top of the O2 masks and established communications.

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Original NASA ASRS Text

Title: An EMB-145 crew detected cockpit smoke so they declared an emergency; completed the QRH and diverted to a nearby airport where black soot was discovered in the battery compartment.

Narrative: The Captain and Pilot Monitoring; noted that there was smoke coming from somewhere around the left side of the flight deck and declared smoke in the cockpit. As Pilot flying; [I] knocked off my headset and dawned my oxygen mask and noted a bluish color smoke filling the cockpit. This was shortly after we had climbed through FL180. I started a level off and the Pilot Monitoring ran the immediate action checklist started the QRH and declared an emergency and asked for lower and a heading to the nearest suitable airport for landing. A major airport was about 20 NM away and we were given direct to the airfield for landing. The Pilot Monitoring dinged the Flight Attendant to let her know that we were diverting and to prepare the cabin. I then stared a decent at about 4;000 FT per minute. ATC pointed out the airport at about 10 miles away and we turned down wind for landing. On the downwind; I noted that the smoke had dissipated. We decided on the visual to the runway backed up by the Localizer. The approach was normal and landing was smooth. After the Captain took over after landing we came to a complete stop and the fire crew inspected the aircraft for any visible smoke or fire damage. We then taxied to a gate with a jet bridge and deplaned all passengers. After we were at the gate the fire crew took a look at the battery compartment and noted that there was black soot inside. Total flight time from takeoff to landing was about 21 minutes.We could not establish clear communications with the oxygen masks on. We put on our headsets over top of the O2 masks and established communications.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.