Ames Procedural
Requirements
APR 1700.1
Last Revised: 06/10/2010
COMPLIANCE IS MANDATORY
Ames Health and Safety Manual
11.1.1 Electrical Shock
11.1.2 Arc-Flash
11.1.3 Arc Blast
11.1.4 Other Burns
11.1.5 Delayed Effects
11.2.1 Hazard Control Hierarchy
11.2.2 Energized Electrical Work Requirements
11.2.3 Authorizing Policy
11.2.4 Hazard Analysis Requirements
11.2.5 Hazard Modes
11.3.1 General Guidelines for Qualification
11.3.2 General Guidelines For Authorization
11.3.3 Specific Qualification And Authorization Criteria
11.3.4 Electrical Distribution Systems (PREMISES WIRING)
11.3.5 Research Apparatus (Utilization Equipment)
11.3.6 Electrical Two-Person Rule
11.3.7 Electrical SAFETY WATCH
11.3.8 Service or Maintenance Contracts (Equipment Subcontractors)
11.4.1 Qualifying background
11.4.2 On The Job Training
11.4.3 Task and site specific Training
11.4.4 Requirements for specific work efforts or tasks.
11.9.1 Written- Operating Procedures
11.9.2 Underground Systems
Chapter 11 covers the NASA Research Park (NRP) & Ames Research Center (ARC) requirements and procedures for designing a safe system and maintaining safe work conditions for personnel, who operate, maintain, or install electrical and related mechanical apparatus and equipment. Adherence to these requirements and procedures is critical to maintaining electrical safety at ARC.
This chapter applies to all electrically qualified employees, participating guests, visitors, students, contractors, subcontractors, vendors, and others (civil servants, research associates, etc.)
Non-compliance with this APR will result in appropriate disciplinary action that may include termination for a civil servant employee or exclusion from the Center for a contractor employee.
Roles for facilities/capital projects:
Lead Electrical Engineer - Code RCE
Serves as the �Subject Matter Expert� for interpretation of this chapter and any required information for analysis as set forth in this chapter.
Health and Safety Manager - Code QH
Serves as the �Authority for Safety� as related to this chapter.
Electrical Safety Board
The Electrical Safety Board will define and review policies and procedures that support electrical safety for the protection of people at NASA Ames.
The Electrical Safety Board also mediates disagreement on interpretation of the information in this chapter, and hears and decides, along with line management, any appeals.
Note: The NEC is revised and a new edition is issued on a three-year cycle. The revised NEC requirements shall immediately be implemented if such implementation will improve the safeguarding of personnel or will protect Ames equipment. Such determinations will be made in consultation with the safety and mission assurance office and the engineering directorates.
The requirements of the latest adopted version of the NEC shall be used for all new electrical work unless there are more stringent requirements imposed by Ames policy.
Definitions and acronyms are located in Appendix �A�.
CAPITALIZED and EMBOLDENED terms are defined in APPENDIX �A�
Supervisors:
Supervisors of electrical workers have the primary responsibility of ensuring a safe working environment. They must:
Line Management
Line managers, by virtue of the delegation of responsibility for all aspects of occupational health and safety through line management, are responsible to assure compliance with all ELECTRICAL SAFETY requirements as defined in the institutions procedures pertaining to all programs, activities, and facilities within their respective areas of responsibility.
Code R
Facilities System Engineering, serving as Authority Having Jurisdiction (AHJ), is responsible for interpretations of NFPA 70, The National Electrical Code. Facilities System Engineering, acting through the Lead Electrical Engineer will:
The Authority Having Jurisdiction (AHJ) for each facility (the Facility Manager) is responsible for installations in their facility.
Code Q
Ensure that all fully qualified workers are trained and qualified according to the requirements of this chapter.
Ensure through a validation process that all the requirements of this chapter are followed.
Accidental contact with EXPOSED electrical parts operating at a VOLTAGE greater than 50 volts to ground, and having a current greater than 5 milliamperes, can cause serious injury or death. Fatal ventricular fibrillation of the heart can be triggered by a current flow of as little as several milliamperes. Severe injuries, such as deep internal burns, can occur even if the current does not pass through the vital organs or nerves.
When an electric current passes through the air gap between two conductors, the temperature can reach 35,000�F. Exposure to these extreme temperatures can result in life threatening burns. The majority of hospital admissions due to electrical accidents are from arc-flash burns, not electrical shocks. Arc-flashes can and do kill at distances in excess of 10 ft.
The tremendous temperatures of the arc cause an explosive expansion of both metal and the surrounding air in the arc path. For example, copper expands by a factor of 67,000 times when changed from a solid into a vapor containing shrapnel. The dangers of this explosion are of high blast pressure wave, high decibel levels of sound and high velocity shrapnel. Finally the material and molten metal is expelled away from the arc at speeds exceeding 700 miles per hour. Arc blasts often cause severe injuries and death.
Other burns suffered in electrical accidents are of two basic types: electrical burns and thermal contact burns. In electrical burns, tissue damage (whether skin deep or deeper) occurs because the body is unable to dissipate the heat caused by the current flow. Typically, electrical burns are slow to heal. Thermal contact burns are those normally experienced from skin contact with the hot surfaces of overheated electric conductors.
Damage to the internal tissues may not be apparent immediately after contact with an electrical current above 50 volts. Delayed internal tissue swelling and irritation are possible. Prompt medical attention can help minimize these effects and avoid death or long-term injury.
Therefore, it is the policy at NASA Ames that all persons who receive a >50 volt electric shock immediately report to the medical services unit for an evaluation. It is highly recommended that the victim not drive himself or herself if possible.
All Contractor and sub-contractor personnel shall be instructed to report all emergencies by calling the NASA Dispatch Office at 911 on Government phones, or 650-604-5555 on cellular phones, pay phones or private phone lines. (Dialing 911 on cellular phones, pay phones or private phone lines will call the City of Mountain View, and delay response.) The Contractor shall post emergency phone numbers at the jobsite. (APR 1700.1 Ch 27.9.8)
**Static shocks are excluded from this policy.
The following hazard control hierarchy will be used to mitigate ELECTRICAL HAZARDS:
11.2.1.2 Administrative Controls
Administrative controls may include, but are not limited to the following:
11.2.1.3 Personal Protective Equipment (PPE)
Qualified workers who are potentially EXPOSED to ELECTRICAL HAZARDs that cannot be controlled through some engineering means must be provided with and use personal protective equipment that is appropriate for the specific work to be performed and the associated hazard level. NFPA 70E defines PPE requirements.
11.2.1.3.1 PPE Use
PPE shall be used to mitigate the hazards of electrical shock and electrical burns from arc-flash when work is to be performed on energized equipment and personnel are within the approach boundaries for shock protection as defined in NFPA 70E, Art. 130.2 and with flash protection boundary for arc-flash as defined in NFPA 70E, Art. 130.3(A).
PPE shall be selected based on the requirements of NFPA 70E, Art 130, Table 130.7(c)(9)(a) defining hazard/risk category for electrical tasks and Table 130.7(c)(10) defining required PPE based on hazard/risk categories
All insulated safety devices shall be rated as PPE and tested, used, and stored as such.
Sufficient protection in the form of rated, insulated tools and insulated protective equipment, such as gloves, blankets, sleeves, shoes, mats, etc., shall be used while working on energized circuits.
11.2.1.3.2 Storage of Protective Equipment
Protective equipment shall be maintained in a safe, reliable condition. The protective equipment shall be visually inspected before each use.
11.2.1.3.3 Testing and Inspecting of Protective Devices
Each organization is responsible for the use and maintenance of protective devices and shall define and follow a process to assure that the equipment meets the following requirements:
11.2.1.4 Safe Work Practices
An electrically qualified person who has been trained and briefed by a knowledgeable supervisor for the specific tasks the supervisor authorizes must apply electrical safe work practices during analysis, diagnostics, and testing, troubleshooting, and manipulative work on ENERGIZED equipment.
11.2.1.5 Working Clearances
At or Below 600 Volts AC Sufficient access and working space shall be provided and maintained about all electric equipment with all covers and guides in place (from 50V to 600V) to permit ready and safe operation and maintenance at Ames. Distance shall be measured from the live parts, if such are exposed, or from the enclosure front or opening if such are ENCLOSED.
Energized or live work requirements are located in Appendix �C�.
All energized working including diagnostics and testing shall follow the guidelines set out in NFPA 70E.
70 E addresses hazard levels and prescribes worker safety controls for a large number of tasks and associated equipment. It cannot address all tasks and all equipment.
NFPA 70E requires that a safety plan shall be executed consisting of:
For specific worker safety requirements refer to the following hazard/risk tables and section 11.2.4, "Hazard Analysis Requirements"
The tables and text in 70E shall be followed unless doing so:
In such cases the employee, their supervisor, and their management (if required) shall define an alternative APPROVED safety plan or standing procedure, that addresses the all pertinent safety issues and defines �equal to or better than� controls and mitigations, to replace those in 70E.
Whenever possible, all electrical work shall be performed on DEENERGIZED circuits. When all reasonable attempts have been made to work on the equipment in a DEENERGIZED state, operations such as diagnostics and testing for voltage, current, or power can be performed on or near live circuits by fully electrically qualified personal trained in all site and facility hazards, mitigations, and all other pertinent policies. Such policies shall include but not be limited to:
All other NFPA 70 E requirements including, but not limited to, work force requirements (# of workers), postings, barricades, barriers, SAFETY WATCHes, and PPE shall be followed.
When complex, extremely hazardous equipment or >50 volts is involved; specific written procedures shall be followed (Standing Procedures, Energized Electrical Work Permit or Job Safety Analysis). Workers shall be trained in the use of these procedures and Job Briefings shall be conducted. These procedures shall give direction to NFPA required work practices and PPE. Where such procedures do not exist they shall be developed, and shall include:
NRP & ARC have adopted National Fire Protection Association (NFPA) 70E, Standard for Electrical Safety in the Workplace. All employees at NRP & ARC shall comply with this standard�s ELECTRICAL SAFETY work practices in addition to following all other requirements of this chapter.
It is NRP & ARC policy to DEENERGIZE live parts, whenever possible, before an employee works on or near them per NFPA 70 E and the Center�s APR 1700.1 chapter 31 (Lockout/Tagout). This is the preferred method for protecting workers from ELECTRICAL HAZARDS. Workers are permitted to work on or near EXPOSED LIVE PARTS only if it can be demonstrated that deenergization introduces additional or increased hazards or is infeasible due to equipment design or operational limitations. ENERGIZED parts that operate at less than 50 volts need not be DEENERGIZED if there will be no increased exposure to electrical burns or to explosion blast due to electric arcs.
11.2.3.1 Job Briefing and Job Planning Checklist
Before starting any diagnostics & test ENERGIZED electrical work having a Hazard Class greater than 50 volts, the workers, must complete a job hazard checklist or similar and the person in charge must conduct a job briefing with the electrically qualified person(s) who will do the work. The briefing may be very simple and verbal, or quite detailed and fully documented, depending on the complexity and hazard level of the job and the background and knowledge of the worker performing the work. Regardless of whether the briefing is verbal or documented, all elements of the briefing form, if applicable must be included.
11.2.3.2 Energized Electrical Work Procedural Steps
It is not feasible to develop a single set of hazard controls for ENERGIZED work that covers every electrical task. The nature and complexity of these controls is dependent upon the combination of the Hazard Class (VOLTAGE and power levels) and the Hazard Mode (risk level) of the ENERGIZED electrical task to be performed. In general, electrical work at NRP & ARC can be organized into six hazard classifications (-1, 0, 1, 2, 3, & 4) according to the degree of energy present.
There are 7 procedural steps that must be completed before any ENERGIZED electrical work is performed:
11.2.4.1 Hazard Classes
The Hazard Class is a function of the potential exposure presented by the VOLTAGE, current, power and stored power or energy available while performing the task.
Because PREMISES WIRING usually presents extremely high fault currents, a separate category is used for Facilities equipment Experimental or R&D equipment is a second hazard category. Finally, batteries appear in a third hazard category.
11.2.4.1.1 Premises/Facilities Hazard Classes
11.2.4.1.2 R&D Energized Hazard Classes:
11.2.4.1.3 Battery Hazard Control Requirements
The Hazard Mode is determined by what work procedure will be performed. The three-task hazard Modes, in order of increasing danger, are:
11.2.5.1 WORKING ON OR NEAR DEENERGIZED Circuits or Components. In this mode all operations are conducted in a verified DEENERGIZED state. All external sources of electrical energy are disconnected or controlled by some positive action (for example, with a locked and tagged out circuit breaker), and all internal energy sources are rendered safe.
11.2.5.2 Performing ENERGIZED Diagnostic and Test Procedures on Circuits or Components.
This mode includes measurements and observation of equipment functions, without MANIPULATION, which are conducted with the equipment ENERGIZED and with some or all-protective barriers removed and interlocks bypassed. Such work requires completion of a Job Planning Checklist and job briefing, which may require completion of an Energized Diagnostics & Test Job Briefing Form that provides additional information including:
11.2.5.3 Performing ENERGIZED Manipulative work.
Performing ENERGIZED manipulative work on circuits or components is the highest hazard work mode. Manipulative operations are defined as physically manipulating any ENERGIZED components or any time the worker physically enters the PROHIBITED APPROACH BOUNDARY. Probing ENERGIZED circuitry with test equipment is not manipulation unless the workers body passes into the PROHIBITED APPROACH BOUNDARY. Such work in excess of 50 volts is a high-risk situation and is permitted only when formally justified and APPROVED. ENERGIZED manipulative work must be conducted under close supervision and control. This requires completion of an electrical safety checklist and an energized work permit.
Only those persons who are both electrically qualified and authorized may install, fabricate, repair, test, calibrate, or modify electrical or electronics wiring, devices, systems, or equipment.
An electrically qualified and authorized person is an individual formally recognized by Center Management as:
A person can be considered qualified and authorized with respect to certain equipment and methods but not authorized for others.
Qualification for electrical or electronics work is determined by the employee�s Supervisor, and could be based on a combination of institutional training (including required periodic retraining), formal electrical trade, military, college or other training, work experience, and on-the-job training. Formal training can be the completion of apprenticeship or comparable training. Experience may be a combination of, or include, formal technical related education courses, hand-on field or classroom lab work that may or may not result in licenses or certifications.
On-going electrical and electronics training should include an annual review of institutional policy and requirements pertinent to the employee�s work assignment as well as the Center�s Lockout/Tagout Program (APR 1700.1 Chapter 31). For specific work requirements the supervisor may require additional classes to the employee�s training course list as deemed important by that supervisor.
Authorization to perform electrical or electronics work by an employee is determined by the employee�s Line Management and Supervision, and is based on the ability of the employee to perform a specific task safely.
11.3.3.1 On-The-Job Training
On-the-job training for specified equipment or classes of equipment must be documented to ensure that training is adequate and consistent for all employees with similar tasks. This documentation must be reviewed and APPROVED by a person who is knowledgeable in safe electrical work practices, and is familiar with the hazards involved in the apparatus. This training shall cover:
11.3.3.2 Task-Specific Training Criteria
Supervisors shall use the following guidelines to determine whether an individual is qualified to perform specific electrical work. Different subsets of these criteria shall be selected according to the exact nature of the task; however, some analysis must always be performed, no matter how minor the job.
The supervisor shall authorize the employee to perform the work task only if he/she is satisfied that all relevant criteria are met. Sample criteria for an employee�s qualifications to be considered is listed below:
If the individual will be permitted to work within the LIMITED APPROACH BOUNDARY of EXPOSED ENERGIZED parts operating at 50 volts or more the individual shall at a minimum be additionally trained in all the following:
Only electrically qualified and authorized personnel are allowed to perform electrical wiring or other work directly connected to any facility electrical distribution system (PREMISES WIRING as defined by the NEC). PREMISES WIRING includes that portion of utilization equipment that is permanently connected (hard-wired) to the facility electrical distribution system, viewed from the utilization equipment�s first disconnect (or circuit breaker) looking backward into the PREMISES WIRING.
Electrically qualified and authorized electrical workers may only do connection to and diagnosis and repair of, circuit breakers in building electrical panels. If there is a question about what differentiates a facility system (PREMISES WIRING) versus utilization equipment, consult the Lead Electrical Engineer Code RCE and/or Electrical Shop Supervision.
Only QUALIFIED Persons may fabricate, modify, install or repair electronic or electrical equipment used at NRP & ARC. Supervisors are responsible for ensuring that only QUALIFIED PERSONS under their supervision are assigned to work on electronic or electrical equipment. The supervisor shall ensure the qualifications of these employees are documented. Nonqualified employees, including researchers, may operate or reset circuit breakers under the following conditions:
Certain work may require two QUALIFIED PERSONS. This occurs when work is considered electrically hazardous, per NFPA 70E, OSHA or the work supervisor.
When the "Two-Person Rule" is required, both workers must be present at the work site, and each worker must be aware of the other worker's tasks and must:
Note: Both workers may perform separate work tasks so long as safety is not compromised.
Non-Electrical personal performing electrical lockout/tagout for mechanical equipment operating at less than 600 volts shall be trained in NASA Ames Lockout/Tagout and all pertinent task specific information including how to shut down equipment in event of an emergency. These persons can fill two-person rule functions for lower hazard efforts.
11.3.6.1 Exemption to Two Qualified Persons
Under limited conditions, the Electrical Two-Person Rule may allow for a second person that is not a qualified person. During the briefing process the QUALIFIED PERSON will assess the qualifications of the second person to determine that the work may proceed safely. The second person may not enter the LIMITED APPROACH BOUNDARY or the FLASH PROTECTION BOUNDARY. Additionally, the second person must be briefed in emergency procedures and the electrical work being performed and must follow any additional guidelines per NFPA 70 E.
Note: This exemption only applies to the Two Person Rule, and shall not be used when a SAFETY WATCH is required.
A SAFETY WATCH is a more stringent hazard control measure than the Two-Person Rule and must be implemented when there are grave consequences from a failure to follow safe-work procedures. This occurs when work is considered high-hazard electrical work.
When a SAFETY WATCH is required, the SAFETY WATCH must be a qualified person who is responsible for monitoring the qualified person(s) doing the work. A SAFETY WATCH must:
Third-party service companies or individuals may provide installation or maintenance of commercial equipment under purchase orders, service contracts or blanket purchase orders for service. A construction manager or property custodian of the equipment needing service must be aware of the hazards, nature and extent of maintenance to be done on the equipment when engaging outside contractors and vendors. These workers must follow the safety requirements and procedures of their employers and NFPA 70E, which must provide a level of ELECTRICAL SAFETY consistent with this Chapter.
The equipment custodian may impose additional safety requirements on the work to ensure that the work can be done safely and not present an unexpected hazard to the contract worker, or other personal in the area. This may include providing additional safeguards such as protective barriers, posting a qualified person at the work site to control access, or other safety measures as may be required to ensure safe working conditions.
All subcontractor and vendor employees must be informed of NASA Ames electrical safety policy by means of a one-page vendor statement. This statement to be provided by the project manager prior to start of work and at the time of safety orientation.
Object criteria shall be established for qualification (union apprenticeship, AA degree, military experience, other training program, or experience in lieu of.) site training, government training, etc.
Training shall include site and equipment specific information, including safety plans, standing procedures, and acceptable work practices and requirements.
Prior to performing work on electrical equipment, qualified persons shall be trained in and familiar with the safety-related work practices and procedures (including applicable emergency procedures, lockout/tagout, etc.), and other safety requirements that pertain to their job assignments. This training must be documented and can be accomplished in classroom or on the job.
Each organization responsible for working on electrical systems must establish policies and procedures to define qualification of their workers. Technical training shall be documented and shall meet the requirements of the workers job description.
11.4.3.1 Safety Training
The direct supervisor of any person who works with electrical equipment shall ensure that the person has completed the minimum safety training defined below. The level of safety training shall be based on the level of electrical risk and hazard to which the worker will be exposed.
11.4.3.2 Minimum Training
Personnel who work with electrical equipment at NRP & ARC should complete as a minimum the Ames training courses listed below.
Registration for these courses is available at http://dq.arc.nasa.gov/qh/training/ or by contacting the Ames Safety Training Administrator at X4-2056.
Required training includes:
Note: Persons who have not completed the electrically qualified person training can work under an escort condition. The responsibilities of the escort are to ensure that the effected worker understands all the hazards, controls, and any additional Center policies before the work begins. The escort or his designee must be contactable to provide further information as needed.
11.4.3.3 Retraining
A worker shall be retrained when:
Supervisors shall insure that employees are familiar with all safety and production work practices and hazards relating to assignments. This training can be accomplished through group safety meetings, job safety meetings, written local policies, standing procedures and other methods. These trainings must include, but are not limited to, site and equipment specific concerns.
All work at NRP and ARC shall be authorized by one of the following efforts:
System Documentation required includes:
Energized Electrical Work Approvals (briefings, permits, switching tags, specific procedures, etc.) shall be maintained by the supervisor of the person(s) performing the work for at least three years.
Energized Electrical Work Approvals shall be made available, upon request, to Code Q personnel for documentation.
Training records shall be kept on file for a period in accordance with NRP & ARC records retention policies.
Qualification determination records (resumes, job applications, military training records, on-the-job training records, etc.) shall be kept on file for a period in accordance with NRP & ARC records retention policies.
Construction, Maintenance and Service shall comply with this chapter and other requirements and guidelines.
All employees, contractors and subcontractors, visitors, and guests shall comply with NASA Ames policies for permits prior to any work effort.
All grounding shall be achieved in accordance NFPA 70 (NEC), IEEE, NEMA, ANSI, ISA, NETA, and other NASA Ames standards and policies.
Use of Nationally Recognized Testing Laboratory (NRTL) APPROVED equipment is required or the sites Authority Having Jurisdiction (AHJ) can accept equipment and apparatus as safe to operate using objective written criteria from above.
All equipment, cords, apparatus, and components shall be used according to the manufactures intended use or the sites Authority Having Jurisdiction (AHJ) can accept equipment and apparatus as safe to operate using objective written criteria.
Each facility with complex or high-energy systems shall have written operating procedures to ensure the safety of personnel and the protection of equipment. These procedures include, but are not limited to, operating sequences, safety precautions, and emergency actions required.
No excavation may be made for any subsurface work without first obtaining clearance from the Ames Facilities Engineering Branch or Plant Engineering Branch.
ACCESSIBLE (as applied to equipment): Admitting close approach; not guarded by locked doors, elevation, or other effective means.
ACCESSIBLE, READILY: Capable of being reached quickly for operation, renewal, or inspections without requiring those to whom ready access is requisite to climb over or remove obstacles or to resort to portable ladders, and so forth.
APPROVED: Acceptable to the authority having jurisdiction (AHJ).
BUDDY SYSTEM (Two man rule): The practice of employing a second person directly observing the operation, is mandatory whenever electrical work is to be performed on exposed, energized circuits of 251 volts (phase-to-phase) or higher. The person shall be a Qualified Industrial Person.
CARDIOPULMONARY RESUSCITATION (CPR): A procedure attempting to restore normal breathing and heart beat after a cardiac event that includes the clearance of air passages to the lungs and heart massage by the exertion of pressure on the chest.
DEENERGIZED: Achieving the verified zero energy state by opening every electrical connection to an electrical source of potential difference and from electrical charge, not having a potential different from that of the earth.
ELECTRICAL HAZARD: A dangerous condition such that contact or equipment failure can result in electric shock, arc flash burn, thermal burn, or blast injury.
ENCLOSED: Surrounded by a case, housing, fence, or wall(s) that prevents persons from accidentally contacting energized parts.
ELECTRICALLY SAFE WORKING CONDITION: The goal is the verified zero energy state. Energized at less than 50 Volts and low amperage or verified de-energized, locked and tagged, tested to ensure the absence of voltage, and grounded (if deemed necessary).
ELECTRICAL SAFETY: Recognizing hazards associated with the use of electrical energy and taking precautions so those hazards do not cause injury or death.
ENERGIZED (see also live parts): Electrically connected to a source of potential difference (voltage). Connected to a source of electrical power.
ENERGIZED ELECTRICAL WORK PERMIT: A management APPROVED, written permit required by NFPA 70E to work on energized equipment that cannot be placed in an electrically safe work condition for the task to be attempted (diagnostics and testing).
EXPOSED (as applied to energized parts): On or near capable of being inadvertently touched, or approached nearer than a safe distance by a person, including conducting material in contact with that person. This also applies to equipment and apparatus that is not suitably guarded, isolated, or insulated.
FAIL-SAFE: Any and all system or component failures will not create an unsafe condition. The capability to go to a predetermined safe sate (i.e., minimum energy or minimized hazard condition) in the event of a specific malfunction.
FIELD VERIFIED (as applied to electrical configuration-controlled drawings): Validate that drawings accurately depict the configuration of installed systems or equipment, by functional and visual comparison. May also be accomplished by point-to-point wire checks. Point-to-point wire checks require ringing out the wiring between points of termination and are usually done during installation prior to putting system into service.
FLAME-RESISTANT (FR): The property of a material whereby combustion is prevented, terminated, or inhibited following the application of a flaming or non-flaming source of ignition, with or without subsequent removal of the ignition source.
FLASH HAZARD: A dangerous condition associated with the release of energy caused by an electric arc.
FLASH HAZARD ANALYSIS: A study investigating a worker�s potential exposure to arc-flash energy, conducted for the purpose of injury prevention and the determination of safe work practices and the appropriate levels of personal protective equipment (PPE).
FLASH PROTECTION BOUNDARY: A calculated burn protection boundary for an arc blast event around a potentially energized system which, when crossed, requires the use of flame resistant (FR) clothing and personal protective equipment (PPE) and work practices by the qualified or escorted person crossing the boundary. These controls are prescribed in NFPA 70 E.
FUNCTIONALLY VERIFIED (as applied to electrical configuration controlled drawings): Drawings accurately depict the configuration of a functional system or equipment and are verified by operational evaluation.
GROUNDED: Connected to earth or to some conducting body that serves in place of the earth.
GUARDED: Covered, shielded, fenced, ENCLOSED, or otherwise protected by means of suitable covers, casings, barriers, rails, screens, mats, or platforms to protect against the likelihood of approach or contact by persons or objects to a point of danger.
INCEDENT ENERGY: The amount of energy impressed on a surface, a certain distance from the source, generated during an electrical arc event. One of the units used to measure incident energy is calories per centimeter squared (cal/cm2).
INSULATED: Separated from other conducting surfaces by a dielectric (including air space) offering a high resistance to the passage of electric current.
JOB SAFETYT ANALYSIS (JSA): A required document prepared to help workers and management review the hazards and safety precautions required for each job.
LABLED Equipment or materials to which has been attached a label, symbol, or other identifying mark of an organization that is acceptable to the authority having jurisdiction and concerned with product evaluation, that maintains periodic inspections of production of labeled equipment or materials, and by whose labeling the manufacturer indicates compliance with appropriate standards of performance in a specified manner.
LIMITED APPROACH BOUNDARY: An approach limit at a distance from an exposed live part within which a shock hazard exists. Qualified electrical personal as a part of the authorized work effort may cross this boundary in appropriate PPE, using prescribed safety and work practices from NFPA 70E. Qualified industrial person(s) in appropriate PPE may cross this boundary if deemed a necessary and authorized part of the work effort only if escorted by the above qualified worker.
LISTED: Equipment, materials, or services included in a list published by an organization that is acceptable to the authority having jurisdiction and concerned with evaluation of products or services, that maintains periodic inspection of production of listed equipment or materials or periodic evaluation of services and whose listing states that the equipment, material or services either meets appropriate designated standards or has been tested and found suitable for a specific purpose.
LIVE (ENREGIZED) Parts: Intentionally and unintentionally energized conducting materials or components.
Nationally Recognized Testing Laboratory (NRTL): Certain private sector organizations recognized by OSHA as an NRTL. That recognition signifies that the organization has met the necessary qualifications specified in the OSHA NRTL program. The NRTL determines that specific equipment and materials (products) meet consensus-based standards of safety to provide assurance that these products are safe for use in the U.S. workplace.
LOCKOUT/TAGOUT (LOTO): Reference APR 1700.1 chapter 31 and OSHA 29 CFR 1910.147. The control of hazardous energy by engineered isolation from the feed source. A complete step by step procedure that when completed provides a verified isolation from all potentially harmful energy to human personal. This action involves identification of all hazardous energies, verified mitigation and isolation from harmful sources, and the application of locks and tags to insure that the system remains safe.
MANIPULATIVE ENERGIZED ELECTRICAL WORK: Is electrical work above human hazard level that includes moving of conductors, components, or other exposed �on or near� conditions. Unavoidable diagnostics and testing are excluded from this definition.
OVERLOAD: Operation of equipment in excess of normal, full-load rating, or of a conductor in excess of rated ampacity that, when it persists for a sufficient length of time, would cause damage or dangerous overheating. A fault, such as a short circuit or ground fault, is not an overload.
PERSONAL PROTECTION EQUIPMENT, Apparel, and tools deemed to comprise a sufficient protection system for a given set of hazards. PPE can include but is not limited to rubber gloves and other hand protection, foot protection such as boots, eye protection, hearing protection, hardhats, face shields, protective arc-flash clothing, hoods, flame resistant clothing, etc., used to protect a person from electrical shock and arc-flash hazards.
POTENTIALLY ENERGIZED: Electrical equipment or circuits capable of containing electrical energy that has not been locked out, tagged out, and verified as de-energized by proper testing methods.
PREMISES WIRING (SYSTEM): The interior and exterior wiring, including power, lighting, control, and signal circuit wiring together with their associated hardware, fittings, and wiring devices, both permanently and temporarily installed, that extends from the service point or source of power to the outlet(s). Such wiring does not include wiring internal to appliances, luminaries (fixture), motor, controller, motor control center and similar equipment.
PROHIBITED APPROACH BOUNDARY (On or near). An approach limit.
QUALIFIED ELECTRICAL PERSON: One who has skills and knowledge related to the construction, installation, maintenance and operation of the electrical equipment and installations and has received safety training on the hazards involved. Recommend a defined training profile.
QUALIFIED INDUSTRIAL PERSON: A person trained in basic industrial safety including but not limited to:
RESTRICTED APPROACH BOUNDARY: An approach limit at a distance from an exposed live part within which there is an increased risk of shock and burn, due to electrical arc combined with inadvertent movement, for personnel working in close proximity to the live part.
SAFETY WATCH: A second fully qualified person with responsibilities to control work area and work practices.
SERVICE POINT: The point of connection between the facilities of the serving utility and the PREMISES WIRING (point to reference).
SHOCK HAZARD: A dangerous condition associated with the possible release of energy caused by contact or approach to live parts.
VERIFIED DEENERGIZED (See Also: Electrically Safe Work Condition). 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.
VOLTAGE: The potential difference between any two or more conducting points or conductors.
VOLTAGE NOMINAL: A nominal value assigned to a circuit or system for the purpose of conveniently designating its voltage class (120/140, 480/277, 600, etc.). The actual voltage at which a circuit operates can vary from the nominal within a range that permits satisfactory operation of equipment.
| AHJ: | Authority Having Jurisdiction |
| ANSI: | American National Standards Institute |
| ARC: | Ames Research Center |
| CPR: | CARDIOPULMONARY RESUSCITATION |
| EH&S: | Environment, Health & Safety |
| ESB: | Electrical Safety Board |
| J: | Joules (watt-seconds) |
| LOTO: | Lockout/Tagout |
| mA: | Milliamperes |
| NEC: | National Electrical Code. See also NFPA 70 |
| NESC: | National Electrical Safety Code |
| NFPA: | National Fire Protection Association |
| NFPA 70: | National Electrical Code. See also NEC |
| NFPA 70E: | Standard For Electrical Safety in the Workplace |
| NRP: | NASA Research Park |
| NRTL: | Nationally Recognized Testing Laboratory |
| OSHA or Fed OSHA: | Federal Occupational Safety and Health Administration |
| PPE: | Personal Protective Equipment |
| V: | Volts |
| W: | Watts |
Shock Protection Boundaries (Reference: 2004 NFPA 70E, Table 130.2)
Arc Flash Protection Boundary (Reference: 2004 NFPA 70E, Article 130.3)
Limits of Approach Diagram
Portable Equipment Grounding: The cases of all portable electrical motor-driven hand tools must be grounded by use of standard three-prong plugs and receptacles. The cases or frames if all other electrical equipment supplied with 50V or greater must be connected to ground, except as follows:
Devices operated solely from self-contained batteries.
Extension Cords: Extension cord usage shall abide by the restrictions for temporary wiring. An extension cord shall have adequate current-carrying capability to handle the maximum current draw of the electrical device serviced. Compare the ampere rating of the electrical devices with the rating of the extension cord or consult a qualified electrical worker for assistance. Extension cords must be of the three-pronged grounded variety and suitable for the conditions of use and location (a non-corrosive dry location.) Where extension cords are utilized, they shall not be:
Use of NRTL Devices: Use only NRTL (ex. UL) APPROVED electrical devices.
High Current Equipment: High current equipment (e.g., microwave ovens, space heaters, and coffee pots) shall be plugged directly into wall receptacles. Daisy Chaining: Daisy chaining (i.e., linking two or more extension cords) is prohibited.
Surge Protector Power Strips: A surge protector power strip is a special type of extension cord that is intended to protect computers and related equipment from damaging power fluctuations. Surge power strips are allowed for use with computers and related equipment, and should not be used with other electrical equipment.
Cords Used in Outdoor or Wet Locations: All cords used in outdoor or wet locations shall utilize integral or separate Ground Fault Circuit Interrupters (GFCI) for shock protection.
Each facility must have written operating and maintenance procedures to ensure the safety of personnel and the equipment. These procedures must include acceptable work practices, safety concerns and actions, and emergency shutdown procedures and response actions as required. At least annually, these procedures shall be reviewed and updated as needed.
The Facility Service Managers shall coordinate with Project Managers for the repair or overhaul of major research equipment, which requires partially or totally disabling of the research operations of a facility in accordance with the requirements of this chapter.
When working on the new installation, repair or overhaul of electrical equipment or system, the work shall be coordinated with the Ames Facility Service Manager (FSM), Maintenance Supervisor, or the Operating Manager of the Facility.
When work is to be done to remove old or obsolete equipment, the electrical wiring, conduit, and control boxes must be removed all the way to the source of feed. After the equipment has been removed, the electrical wiring diagrams, schematics, etc., must be updated to show the changes.
Demolition and safety plans shall utilize approved techniques such as LOTO or air gaps to insure the safety of workers removing equipment and/or apparatus.
Shall be maintained per applicable NFPA and ANSI standards.
Specifications for electrical work that requires an interruption of electrical service to a facility must include a clause that requires the contractor to notify the Ames Contracting Officer prior to making connection(s) into any part of the Ames Research Center's electrical power distribution system. The application shall state the date, time, location, service involved, and when the connection is to be made. Approval must be obtained before the circuit is DEENERGIZED
Grounding of Equipment
Protective Grounding - General
Protective Grounding � Transformers
Protective Grounding of Current and Potential Transformers
Protective Grounding of Coupling Capacitors
Protective Grounding � Underground Cables
General Requirements
Underground Cables
Racking in or out of circuit breakers shall follow the requirements set forth by the manufacture.
The organizations responsible for racking circuit breakers shall have defined policies and procedures for these operations. Certified operators who are fully qualified workers and have completed the appropriate training shall be the only personnel who perform racking operations. Appropriate PPE shall be selected and used during racking operations. In addition:
Areas of Responsibility
The Ames Facilities Engineering Branch shall maintain documentation that delineates areas by branch responsibilities for the high voltage distribution systems.
The Ames Electric Power Office (EPRO) shall approve this document.
System Documentation
System Documentation, showing the arrangement, location, and wiring of the electrical distribution and equipment shall be maintained on the job site and be readily available to all authorized personnel involved in the work effort for review of that portion of the system for which they are responsible.
All workers shall use the following Color Coding for indicating lights to be installed in control rooms, switchgear, motor control centers, distribution panels, etc. If a specific facility does not use this color scheme, it must specifically document the color scheme to be used.
Colored caps on indicating lights designating the conditions or position of the contacts on circuit breakers or switches must conform to the following:
The above color-coding of indicator lights is switchgear specific as referenced in IEEE C37.11 and C37.100
Colored caps on indicating lights designating the position of a control valve that allows flow or blocks flow must conform to the following:
The color coding of electrical wiring at NASA Ames shall follow the National Electrical Code and local facility requirements.
All fixed electrical equipment must be ACCESSIBLE for maintenance, repair, and deenergization per the NEC Table 110.26(A)(1) and Table 110.34(A) The minimum clear space around electrical equipment for emergency disconnecting means as indicated by yellow markings on the floor shall be three feet and must be kept clear with a clear path of access.
For High-voltage (above 600V) circuit breaker switchgear refer to NEC Table 110.34(A) which requires a minimum of six feet of clear space at the front and three feet at the rear. Motor control centers, panel boards, and terminal cabinets require a minimum of three feet in front refer to NEC Table 110.26(A)(1)
Qualified workers shall not approach or take any conductive object, within the "approach distance" to an exposed energized part in switchgear, panelboards, electrical substations, or rotation equipment shown below:
Unqualified workers as defined by OSHA shall maintain a minimum clearance of 10 ft from energized lines.
NFPA 70E defines three shock protection boundaries (Limited Approach Boundary, Restricted Approach Boundary and Prohibited Approach Boundary) for persons approaching exposed energized parts. The distances for those boundaries, (based on system voltage) are listed in NFPA 70E, Table 130.2(C). The requirements for crossing the shock protection boundaries by qualified and unqualified persons are defined in NFPA 70E, Art. 130.2,
Unqualified workers as defined by OSHA shall maintain a minimum clearance of 10 ft from energized lines.
Notes:
Any overhead wires and cables shall be considered to be energized line unless it has been verified DEENERGIZED by an authorized and fully qualified worker and is visibly grounded or air gapped.
A person shall be designated to observe clearance of the equipment and give timely warning for all operations where it is difficult for the operator to maintain the desired clearance by visual means.
When electrical distribution and transmission lines have been energized at point of work, the equipment or machines shall be operated proximate to energized power lines per distance identified below.
For lines rated 50 kV or below: Minimum clearance from closest contact point of crane, load, or other projection and energized lines is 10 ft.
For lines rated over 50 kV: Minimum clearance from closest contact point of crane, load, or other projection and energized lines shall be 10 ft plus 0.4 in. for every 1 kV.
Crane with No Load and Boom Lowered:
Lines 50 kV or less shall have a minimum clearance of 4ft.
Lines over 50 kV shall have a minimum clearance of 4ft plus 0.333ft for every 10 kV over 50 kV.
