The chef's hat is called a "toque blanche" (French for "white hat"). It is usually shortened to just "toque" . They are worn because the health department requires restaurant employees to wear a hat or hair restraint of some sort. This prevents hair from falling into the food. A hat also can absorb perspiration from the head before it reaches the plate. The tall hat allows room for air to circulate above the chef's head as well. he white hat has come to serve as a marker of a trained professional chef. The height of the hat represents the rank of the chef.