Arc Suit is a protective equipment worn by personnel working in places where there is a risk of an arc flash. Personnel working with HV equipment in switchyards and in HV panel rooms need to be properly protected against Arc Flash (See Article on Arc Flash). Arc Suit are made of fire and heat resistant materials. These suits can protect the person from the immense heat and energy dissipated during an arc flash. Arc suits are classified on the basis of kJ/sq.cm. This refers to the maximum heat energy that the suit can withstand. The appropriate suit should be selected based on the Arc Hazard Study which will give details of the maximum potential of an arc in a particular location.