Yes indeed, the crash scenes were shot in a CA studio.
PartsRack helped provide --rented!-- some damaged parts which were then painted sapphire blue. Producres removed the good hood and 'crashed' our old hood. They even wanted exploded airbags to add to the realism, but I did NOT see them in the scenes.
Go figure..
FOR SALE: "COLLECTIBLE COFFEETABLE / WALL ART HOOD, AS CRASHED BY DR KOVAC ON ER !!!! " AUTOGRAPHED !
I LOVE MY JOB !!!