I WAS PARKED WITH ENGINE IDLING, AIR CONDITION ON, CONVERSING WITH MY ADULT NIECE, TRANSMISSION IN PARK WITH MY LEFT HAND ON STEERING WHEEL WHEN WITH LOUD BANGING SOUNDS DRIVER SIDE STEERING WHEEL AIRBAG DEPLOYED IN FRONT OF MY FACE AND MY LEFT UPPER EXTREMITY, HITTING MY LEFT ARM AND PUSHING IT AWAY FROM ME AND FRONT PASSENGER DEPLOYED IN MY NIECE'S FACE AND RIGHT UPPER AND LOWER EXTREMITY WITHOUT REASON. I HAD MY SEAT BELT ON WHEN THIS OCCURRED. MY LEFT ARM WAS INJURED BY AIRBAG IMPACT LEAVING SOFT TISSUE DAMAGE, AN ABRASION, RINGING IN EARS AND NECK PAIN. MY NIECE SUFFERED ABRASIONS ON HER RIGHT SHOULDER AND LEGS, RINGING IN HER EARS AND EMOTIONAL TRAUMA. PASSENGER COMPARTMENT (GLOVE BOX) AND ITS CONTENTS WAS EXPELLED HITTING HER LEGS. THE CENTER FRONT CONSOLE ASH TRAY WAS EFFECTED, PUSHED OPEN AND ITS CONTENTS WAS ALSO EXPELLED. I WAS IN MUCH SHOCK BECAUSE OF THIS EVENT. INCIDENT OCCURRED IN AN APARTMENT PARKING LOT.