Electrical procedures Toolbox Talk 2

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Transcript Electrical procedures Toolbox Talk 2

Procedures for work on
Fixed Electrical Installations
Toolbox Talk 2:
Duties of Staff and
Contractors
Main Points:
•
Hazards and risks associated with work on electrical systems
•
Duties of Estates Section electrical staff
•
Approved tools and equipment for use by Estates Section Electrical Staff
•
Rules for contractors working on University electrical systems
On average, 20 people are killed in the UK every year by electrical accidents
whilst at work - most of these accidents are preventable.
The Electricity at Work Regulations 1989 requires precautions to be taken
against the risk of death or personal injury from electricity in work activities.
The purpose of these procedures is to put in place a system of control measures
to prevent injury to University Staff and contractors from the hazards and risks
associated with work on electrical systems at the University.
HAZARDS AND RISKS ASSOCIATED WITH WORK
ON ELECTRICAL SYSTEMS
Electric shock
Electric arcing
Fire
Electrical explosions
Electric Shock occurs when a person makes
contact with a live conductor while
simultaneously in contact with an earthed
object or another live conductor at a lower
potential and current passes through the body.
The effects of electric shock include:
• Muscular contractions causing involuntary gripping of the live
source and being unable to let go.
• Cardiac arrest.
• Electric burns
• Momentary loss of control or balance
Factors in the surrounding environment that
can increase the likelihood of electric shock
include wet or damp conditions or areas where
there is a high proportion of earthed metal in
cramped surroundings.
DUTIES OF ESTATES SECTION ELECTRICAL STAFF
Clerk of Works (Maintenance), Senior Maintenance Electrician, Chargehand Electrician
• Write a Switching Programme.
• Supervise work on or near live conductors which may foreseeably give rise to danger.
• All of the tasks for electricians and assistants.
Electrician
• Work on low voltage lighting, small power equipment and circuits.
• Work on dead low voltage equipment.
• Carry out testing and fault finding on live/dead equipment.
• Work on or near live conductors which may foreseeably give rise to
danger under supervision.
• Work in main low voltage switchrooms under supervision.
Assistants
• Work on dead low voltage equipment under supervision.
M&E Project Engineers
• Write a Switching Programme.
• Carry out an electrical isolation.
• Supervise work on or near live conductors which may foreseeably give rise to danger.
APPROVED TOOLS AND EQUIPMENT FOR USE BY
ESTATES SECTION ELECTRICAL STAFF
The use of unauthorised personal equipment is forbidden.
User checks before using test equipment
• Check the general condition of the test device (including all leads, probes and connectors)
• Check that test equipment has a label indicating that it has been calibrated within the last
12 months.
The equipment must be taken out of use if any defects are found. Defects must be reported
to the Senior Maintenance Electrician or Chargehand Electrician.
Use of ladders and stepladders for electrical work
All ladders and stepladders used by Estates Section
personnel whilst carrying out electrical work must be glass
fibre type. Use of ladders and stepladders must be in
accordance with the procedure for safe use of ladders and
stepladders.
The following inspection regimes will apply to all equipment:
• Users to check each time before use (see above).
• Quarterly inspections of all tools and equipment by Senior Maintenance Electrician/
Chargehand Electrician.
• Equipment used for testing or measuring to be calibrated annually by an accredited
calibration organisation
Question:
1. How often should test equipment be checked?
WRONG
a)
2 years
b)
Check general condition before each use and calibrate annually
c)
5 years
WRONG
d)
6 months
WRONG
CORRECT
Question
What should you do if defects are found with a piece of equipment:
a)
Take it out of use and inform your line manager
b)
Use it anyway
WRONG
c)
Put it away in your toolbox
WRONG
CORRECT
RULES FOR CONTRACTORS WORKING ON UNIVERSITY ELECTRICAL
SYSTEMS
Note: it is the responsibility of the Estates Section representative (Maintenance or
Projects) commissioning the works to explain these rules to the electrical contractor
prior to the works being carried out.
Isolations/de-isolations
• Contractors MUST NOT carry out any isolations or de-isolations on University switchgear. Isolations must be
carried out by Estates Section electrical staff in the presence of the electrical contractor’s competent
representative. The contractor is responsible for checking the safe and secure isolation of all electrical equipment
or circuits to be worked on or which the works could disturb.
• Contractors must carry out their own tests to confirm that equipment or circuits they will work on or could
disturb are dead.
• The contractor’s padlock must be applied to all equipment or circuits that they are going to work on. In cases
where this is not possible (i.e. only one padlock can be applied) then a lock-out box will be used. UoA electricians
will apply their padlock to the circuit, the key will then be put into a lock-out box. The contractor will then apply
their padlock to the lock-out box along with a second padlock applied by the UoA electricians.
• Testing equipment used by contractors must be marked to indicate that it has been calibrated within the last 12
months.
• Prior to de-isolations being carried out, contractors MUST forward copies of the dead tests required by BS7671:
2008 (IEE Wiring Regulations 17th Edition) for the work they have carried out to Estates Section.
Scope of works
Contractors MUST NOT deviate from the scope of works agreed with the Estates
Section representative commissioning the works.
Redundant cabling
Only electricians may cut electrical cables.
Electrical cables may only be cut if they can be traced back to their source, the source
must be securely isolated.
Cables which are cut must be stripped out, if this is not possible then the Estates
Section representative commissioning the works must be informed.
Refer to Section 6.0 of these procedures for details on the checks to be carried out
when tracing cables.