Terms and definitions

Here is a list of important terms and definitions used in WESR.

A
Access Agreement
A safety document clearly defines the limits of work and limits of the work area within which non-electrical work may be carried out and specifies necessary precautions.
Authorisation
Formal approval in writing or instruction.
B
Barrier
Temporary device intended to remind people of danger and warn against entering particular area.
C
Control area
An area with defined boundaries to other control areas in which the WESR’s are applicable.
Control responsibility
The responsibility delegated to an individual to perform switching measures within a well-defined control area.
D
Dead working
Work activity on electrical installations, which are neither live nor charged, carried out after having taken all measures to prevent electrical danger.
Delegated PCEI
A skilled person, nominated in writing, who is in charge of switching operations within a specified area.
E
Earthing for work
Safety measure for work by earthing and short-circuiting with equipment designed for the purpose.
Electrical Safety Officer Vattenfall BA Wind (ESO)
Nominated and authorised Person who is a Member of the Electrical Safety Board to ensure the legal transparent, Safe and aligned Electrical Organisation.
Electrical hazard
Source of possible injury or damage to health in the presence of electrical energy from an electrical installation.
Electrical injury
Death or personal injury from electric shock, electric burn, arcing, or from fire or explosion initiated by electrical energy caused by any operation of an electrical installation.
Electrical installation (System)
All the electrical equipment that is used for the generation, transmission, conversion, distribution and use of electrical energy.
Electrical work
Work on, with or near an electrical installation such as testing and measurement, repairing, replacing, modifying, extending, erecting, maintaining and inspecting.
Enclosure
Part providing protection of equipment against certain external influences and, in any direction, protection against direct contact.
Equipotential bonding
Electrical connection which equalizes voltage between parts that may become charged at different levels of voltage at the work location (for example, by induction).
Extra-low voltage ELV
Normally not exceeding 50 V alternating current (a.c.) or 120 V ripple free direct current (d.c.) whether between conductors or to earth.
F
Four-eye-principle
A control mechanism requiring that, an activity, must be controlled (reviewed and double checked) by a second individual that is independent and competent.
H
High voltage HV
A potential normally exceeding low voltage.
I
Immediate Supervision
Supervision by a person who is continuously available at the location where work or testing is in progress and who attends the work area as is necessary for the safe performance of the work.
Instructed person
Person adequately advised by a skilled person to enable him or her to avoid dangers which electricity may create at the work location.
Insulating covering
Rigid or flexible cover made of insulating material used to cover live and/or unenergized parts and/or adjacent parts in order to prevent accidental contact.
L
Live working
All work in which a worker deliberately makes contact with live parts or reaches into the live working zone with either parts of his or her body or with tools, equipment or devices being handled.
Live working zone
Space around live parts in which the insulation level to prevent electrical danger is not assured when reaching into or entering it without protective measures.
Low voltage LV
A potential not exceeding 1000 V ac or 1500 V dc between conductors, or 600 V ac or 900 V dc between a conductor and earth.
N
Non-electrical work
Work near to an electrical installation such as construction, excavation, cleaning, painting, etc.
O
Operation
All activities including work activities necessary to permit the electrical installation to function.
Operational procedures
Limited and short duration measures carried out where the electrical hazard is  as far as reasonably practicable prevented due to installation design and the use of suitable tools and equipment.
Ordinary person
Person who is neither a skilled person nor an instructed person.
P
Permission to start work
Direct instruction to the workers at work location to commence work after all safety measures are taken.
Permit to work
A safety documentspecifying the equipment to be worked on, the work to be carried out and the actions taken to achieve safety from the system.
Person in control of a work activity (PCWA)
Person nominated and authorised, with the ultimate responsibility for the work activity at work location.
Person in control of an electrical installation during work activities (PCEI)
Nominated person who is responsible during work activities for the safe operation of the electrical installation.
Person responsible for an electrical installation (PREI)
Nominated person with the overall responsibility to ensure the safe operation of the electrical installation by setting rules and organisation or framework.
Personal Supervision
Supervision by a person such that the supervising person is at all times during the course of the work or testing continuously observing and in the presence of the individual being supervised with the ability to intervene. When individuals are working at height, supervision can be given at ground level providing verbal and visual communication is maintained at all times. This level of supervision shall ensure individuals are not exposed to danger.
Portable equipment for earthing and short-circuiting
Equipment that is portable and is manually connected to parts of an electrical installation for earthing and short-circuiting purposes.
Potential difference
A voltage (potential) difference between parts of an electrical installation, between electrical installations, or between an installation and earth.
R
RISK-W
Risk management carried out at the work location.
Risk
Combination of the probability and the degree of the possible injury or damage to health of a person exposed to a hazard or to hazards.
Risk Assessment Method Statement (RAMS)
A Risk Assessment and Method Statement carried out at the planning stage of the work activity.
Risk management
The co-ordinated activities of controlling risks by assessing, treating or eliminating them.
S
Safe communication
Secure transfer of information with the characteristics of being clear, logged, repeated and traceable.
Safety distance
A minimum distance at which persons are considered safe from the electrical hazard of the work location.
Safety from the System
That condition which safeguards persons working on or testing equipment from the hazards that are inherent in the system.
Sanction for Test
A safety document specifying the equipment to be tested, making known the conditions under which the testing is to be carried out and confirming actions which have been taken to achieve safety from the system.
Screen
Any device, which may be insulated or not, which is used to prevent approach to any equipment or part of electrical installation which presents electrical danger.
Skilled person
Person with relevant education, knowledge and experience to enable him or her to analyse risks and to avoid hazards which electricity could create at the work location.
Switching
The operation of circuit breakers, disconnectors/ isolators, fuses or other methods of making or breaking an electrical circuit, and/or the application and removal of earthing for work.
Switching Assistant
A skilled person, nominated in writing, who carries out switching under instruction.
Switching schedule
A written document in a defined format containing details of Switching activities to be carried out in the specified order.
System
Items of Equipment, which are used separately or in combination in any process, associated with the generation, transmission or distribution of electricity.
V
Vicinity zone
Limited space outside the live working zone.
Voltage detector
Portable device used to detect reliably the presence or the absence of the operating voltage and used to verify that the installation is ready for earthing.
W
Work Request
A request for permission to carry out work activities.
Work activity
Any form of electrical or non-electrical work where there is the possibility of an electrical hazard.
Work location
Site(s), place(s) or area(s) where a work activity is to be, is being, or has been carried out.
Work procedures
There are three defined work procedures to make the workplace safe and carry out work in a safe way:
1. dead working
2. working in vicinity of live parts
3. live working.
Working in the vicinity of live parts
All work activity in which a worker with part of his or her body, with a tool or with any other object enters into the vicinity zone without encroaching into the live working zone.

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