As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TRIP ID NR 934736 WINDSHIELD HEAT WAS TURNED ON AT 10,000 FT WITH AN OUTSIDE AIR TEMPERATURE OF + 2 DEGREES CELSIUS. AFTER REACHING CRUISE ALTITUDE OF FL 250 THE PILOTS SIDE WINDSHIELD SHATTERED. THE CREW DONNED THEIR OXYGEN MASKS AND DECLARED AN EMERGENCY. AN EMERGENCY DESCENT WAS PERFORMED AND THE AIRCRAFT WAS RETURNED TO DEPARTURE. A NORMAL APPROACH AND LANDING WAS MADE. MAINTENANCE REPLACED THE LT PILOTS WINDSHIELD. THE AIRCRAFT WAS RETURNED TO SERVICE.