General Requirements - hdbk109220040021

DOE-HDBK-1092-2004

2.0 GENERAL REQUIREMENTS

This section deals with the reliability and effective maintenance of electrical systems that can be

achieved in part by careful planning and proper design. The training of personnel in safety-

related work practices that pertain to their respective job assignments is outlined.

2.1

ELECTRICAL MAINTENANCE OR REPAIRS

Only qualified persons shall perform electrical repairs. Once a problem is discovered while

troubleshooting or maintaining electrical equipment, any further work on this component or

system must be suspended until the associated corrective actions are processed through a

work control system. It is dangerous for an unqualified worker to attempt electrical repair.

Before any electrical maintenance or troubleshooting is performed, sources of electrical energy

shall be deenergized, except where it is necessary for troubleshooting, testing, or areas that are

infeasible to deenergize. All energy sources shall be brought to a safe state. For example,

capacitors shall be discharged and high capacitance elements shall be short-circuited and

grounded.

2.1.1

WORK ON ENERGIZED/DEENERGIZED ELECTRICAL EQUIPMENT

The first consideration for working on any electrical system is to have the circuit positively

deenergized. All circuits and equipment must be considered energized until opened, tagged,

and/or locked according to an approved procedure and should be proven deenergized by

testing with an approved testing device known to be in proper working order. NFPA 70E refers

to this as an electrically safe work condition and defines it as "a state in which the conductor or

circuit part to be worked on or near has been disconnected from energized parts, locked/tagged

in accordance with established standards, tested to ensure the absence of voltage, and

grounded if determined necessary." The electrical hazard controls identified in NFPA 70E are

intended to protect a person from arc flash and shock hazards. Due to the explosive effects of

some arc events, physical trauma injuries could occur. The personal protective equipment

(PPE) requirement identified in NFPA 70E is intended to protect against physical trauma other

than exposure to the thermal effects of an arc flash.

2.1.2

CONSIDERATIONS FOR WORKING ON ENERGIZED SYSTEMS AND

EQUIPMENT

Qualified employees performing such tasks as electrical repairs, modifications, and tests on

energized electrical systems, parts, and equipment need to comply with the following:

1. Parts to which an employee might be exposed shall be put into an electrically safe work

condition before the employee works on or near them, unless the employer can

demonstrate that deenergizing introduces additional or increased hazards or is infeasible

due to equipment design or operational limitations.

2. Personnel shall not work on energized circuits unless they are qualified to do so, or, for

training purposes, unless they work under the direct supervision of a qualified person.

3. Sufficient protection in the form of insulated tools and insulated protective equipment,

such as gloves, blankets, sleeves, mats, etc., shall be used while working on energized

circuits. (See NFPA 70E)

2-1