(a) Covered work by both qualified and unqualified persons. The provisions of §§ 1910.331 through 1910.335 cover elec-trical safety-related work practices for both qualified persons (those who have training in avoiding the electrical haz-ards of working on or near exposed en-ergized parts) and unqualified persons (those with little or no such training) working on, near, or with the following installations: