NO BURNT ON SAND OR SCALE "TAKE PRECAUSION TO PREVENT WARPINGTIE BARS MUST BE LEFT IN FOR QUENCH AND TEMPER NO VISIBLE CRACKS OR DEFECTS VISIBLE" CRITICAL AREA 1 & 2 CRITICAL AREA 2 WELD MAPS & APPROVAL REQUIRED FOR ALL EXCAVATIONS GREATER THAN 20mm OR 40% OF WALL THICKNESS HEAT RATE 100°C PER HOUR AND HOLD FOR 1HOUR FOR EACH INCH OF THICKEST SETION.