This electrical risk assessment covers all operations related to electrical LV, MV inspection and testing.
Related hazards include:
- Electrocution
- Electric Burn
- Fire
- Explosion
Control Measures
5 Golden Rules to avoid accidents due to electricity:
1. Disconnect completely ( the apparatus on which you are to work)
Live work is too avoided at all times (as far as reasonably practical.)
Request isolation of power source from owner/occupier, isolate power source outside normal hours of premises and provide protection from/isolate sections of equipment and/or phases being worked on e.g. Distribution boards, Form 4 boards. “Request for Isolation” Form.
2. Secure against re‐connection (the apparatus by LOTO).
Isolated circuits must be locked off and tagged out. Client procedures may be used where they are equivalent to procedures.
Where live work is unavoidable a written method statement must be produced and a permit to work must be obtained.
Power On, Lock Out Tag Out and Electrical Permit To Work Procedures to be used and followed.
3. Verify that the disconnected apparatus is dead (check for the absence of voltage with a voltmeter)
Always check isolation with voltmeter
4. Carry out earthing and short circuiting (Stored energy in capacitors).
Verify again with voltmeter.
Dissipate potentially charged equipment to earth.
Always ensure / verify isolation with voltmeter.
5. Provide protection against adjacent live parts
Access to live conductors is to be strictly controlled and limited to authorized competent electricians.
Equipment covers and doors are to be closed at secondary side of equipment under test. Keys are to be kept in Key Box in office.
Tester/Electrician to remain at live end of circuit under test.
All unauthorized persons will be restricted from switch rooms, test zones and warned of hazards appropriately.
Access to switch rooms must be limited to authorize persons only.
Circuit routes will be walked down prior to test to ensure that no work is ongoing on the circuit under test.
Equipment covers and doors are to be closed and guards refitted to machinery prior to this type of work is commencing.
Erect signage, warning people, of presence of electricity / greatest voltage present.
Testing and Commissioning:
Live work to be carried out by authorized competent electricians.
Typical PPE may include Full Face Visor, Helmet, Live Work Gloves, Insulated Mat, Insulated Safety Boots and Arc Protective Overalls.
Electricians are not permitted to work on live circuits unaccompanied.
Buddy system and radio contact to be maintained at all times.
Electrical test equipment will be insulated, fused and have valid calibration certificates.
Electricity Supply Authority seals will not be broken and final connections will not be made without written authority.
All circuits being worked on will be treated as live until verified using voltmeter.
Supervisors/Foreman will ensure that all field wiring is terminated before cables are terminated at their power source.
Otherwise power supplies must be isolated.
Distribution boards are controlled by testers until testing successfully completes.
No unauthorized person is allowed access to DB until certificate is issued to supervisor.
No other person is authorized to power up circuits under test.
Commissioning electricians will be provided with all necessary information prior to starting testing and commissioning e.g. Schematic drawings, scope of work, restrictions, hazards and residual risks.
Lock Out Tag Out Safety Procedure
It is the responsibility of the authorized person applying LOTO to perform & complete a Safe plan of action (SPA) and identify the hazards and control measures in place at the isolation points and select an appropriate LOTO device that does not introduce or create a hazard.
Apply the LOTO device so that it locks the energy isolating device in the off position. Fix the tag directly to each lock.
Affected employees or clients reps shall be notified by the authorized employee of the application and removal of lockout devices or tag out devices.
Dissipate, drain, or safely release any stored or residual energy in the system after lockout.
Verify that all sources of hazardous energies have been isolated.
Inspect the work area to ensure that all nonessential items, tools, etc., have been removed from the danger zone.
Check that all the guarding and safety controls have been properly replaced.
LOTO Preparation for Re-energizing
Notify “Affected Employees and Client Reps” and ensure that all personnel are in a safe location before reenergizing.
Inspect the work area to ensure that all nonessential items, tools, etc., have been removed from the danger zone.
Check the tags before removal, and then remove the LOTO locks and tags.
Re‐energize the equipment/system according to start up procedures.
LOTO Lock and Tag Temporary Removal
Clear equipment or area of tools and materials.
Remove “Affected Employees and Client Reps” from equipment area.
Remove LOTO devices.
Energize and proceed with testing or positioning.
De‐energize all systems and reapply energy control measures in accordance with procedures.
LOTO Tags:
Durable tags, which will not deteriorate under work conditions, shall be used whenever a lock is placed.
The tags must contain at a minimum, the following information: Employee’s name and phone number
Legend such as the following: Do Not start, Do Not Open, Do Not Close, Do Not energize, Do Not Operate
If an energy source cannot accept a lock (tag out only), the tag must contain a warning against hazardous conditions if the Cable, machine or equipment is energized.
Wires, tie wraps, or cords shall be used for securing the tags to the energy control point and must be able to withstand 50‐lb of force.
Supervisors/Managers shall:
Ensure that only authorized employees, who are qualified and trained, apply and remove locks and tags.
Ensure that employees who are found to have insufficient skills or understanding of LOTO requirements do not perform LOTO and are retrained.
Implement, manage, and audit personnel for conformance with the Control of Hazardous Energies task.
Ensure that all safety equipment is stocked, stored and maintained in a state of readiness and is available for employee use.
Ensure that any deficiencies or deviations found in the working procedures/specs are corrected.