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Electrical safety systems in engineering industry using what-if analysis.

INTRODUCTION

The failure in electrical system may result in physical damage to property and mainly cause in high risk of electrocution. Regarding electrical safety there have been many solutions and guide to mitigate and reduce the electrical accident. Already Alex albert says in 2013 Safety risk management for electrical transmission and distribution line construction. An electrical power lines has been the largest cause of electrical fatalities in both domestic and in industries and also in engineering industries. In majority construction side because in this field contractors in maintenance of electrical transmission and distribution are in extremely high risk of electrocution. This would help to reduce the electrical bun injury, unexpected injury [1]. The electrocutions occur due to below factor: age, gender, duration of voltage passing in our body, amount of voltage, passage through the body. These factors describe the type of injury that occurred due to electrocution.

Types of electrical protection systems:

1. Over load protection

2. Over voltage protection

3. Type of voltage AC/DC

4. Short circuit protection

5. Earth fault protection

6. No load protection

7. Protection against surges and voltage fluctuation

8. Interlock protection system

Literature Survey:

As already discussed Alex albert say's that electrical contractors involved in the construction and in electrical maintenance lines are at high risk. Finally he suggested that further conducting of research must be help to reduce risk between different activities and prevention method.

In 2013 Manuel Suarez-Cebador accord to him the severity of work place electrical accidents occurs on construction sector. This research enables the safety experts, government officials industries to identify priorities and to design strategies to minimize the electrical accidents in construction and engineering sector.

In 2004 Colominassays that safe grounding system which results in carry and dissipate the electrical current to ground. When fault conditions and to safeguard of people working with machineries which manages equivalent current to the system.

Major Problems in Engineering Industry:

1. In heavy engineering industry the electrical equipment shows accidents like electrical shock, electrical burn, fire & explosion, hazards due to electric welding and cutting.

2. It happens mainly due to overloading, and improper handling of cords, improper loading of electrical equipment's.

3. Worker on direct contact with energized equipment, and improper insulation for damaged cords and also due to improper usage of tools.

4. And finally lack of personal protective equipment's like resistant helmet, rubber gloves, googles, apron etc.,

Methodology:

Definition of What-if Analysis:

It is a brain storming approach that uses road, loosely structured questioning to postulate potential upsets that uses that may result in accident or system performance and to ensure appropriate safeguards against those problems are provided.

[FIGURE 1 OMITTED]

Analysis procedure:

1. Preparing for review

2. Performing the review

3. Documenting the result
Table 2: Work sheet format for what if

What if   Consequences/ hazards   Safeguard & Recommendation


In the 1st column what if type of questions are to be asked.

In 2nd column describes the consequences and hazards arise.

In 3rd column implemented safety systems and additional suggestion to improve.

Result discussion with safe guard & reccomendations What if analysis:

The following is the chart prepared for the purpose the assessment of electrical safety system in the industry
Table 3: Chart for "what- if" analysis related to Electrical Safety.

What if                Consequences/          Safeguard &
                       hazards                recommendation

What if inspection     The current leakage    periodic maintenance
and maintenance is     is not pass on to      is to be done
not done in earth      the earth
pit(as per IS
3043--1987: Code of
practice for
Earthling)

What if the glands     Person in contact      All glands are need
of the motors and      with glands will get   to be dual earthed
control panels in      shock
not dual earthed?
(as per IS
3043--1987: Code of
practice for
Earthling)

What if the doors      The fault current      All doors and fence
and fence of the       may pass to the        need to be earthed
transformer and        attendees
control panel area
is not earthed?

What if the static     Static energy may      Static energy
discharge point for    pass between flowing   discharge point need
men at work is not     medium and men at      to be provided at
provided near liquid   work                   all liquid transfer
transfer area?                                areas.

What if the display    The fault current      Analyzing the earth
fails in relays and    may damage the         nature at that point
circuit breakers?      system when the        and go for chemical
                       earth is too           earthling?
                       resistive

What if excavation     Electrical discharge   Before excavation,
is carried out over    on the excavator       live conductors to
the underground                               be isolated and
earthling electrodes                          earthling points to
and the buried live                           be unearthed-the
conductors?                                   underground earthing
                                              and live lines to be
                                              clearly marked over
                                              the ground.

What if the fire       Fire hazard            Provide suitable
occurs in the main                            fire extinguishers-
substation,                                   Toshiba has one in
transformer yard and                          15mtrs
any of electrical
panels?(Asper IS
2190 -Selection,
installation and
maintenance of
First-Aid Fire
Extinguishers)

What if the gas in     The gas leaks to the   Proper refilling
the gas circuit        atmosphere and         device (eg: Dilo-
breaker (GIS-Gas       deplete the ozone      germany) has to be
Insulated Switch       (SF6-sulphur           used(in Toshiba the
gear)is leaked and     hexafluoride-is a      approximate leakage
what if the gas        ozone depleting        will be 0.1% in a
refilling is not       substance(ODS))        month)
under proper system?

What if the            Electric hazard        Choose Suitable
electrical supply                             rating
lines of an
apparatus is not
provided with
sufficient rating of
either insulation or
current carrying
capacity or voltage
or mechanical
strength?

What if the danger     Persons may get in     Danger notice to be
notice is not          contact with           placed at
provided in the        electric shock         appropriate places
appropriate places?
(As per The Indian
Electricity Rules,
1956-Chapter Iv-
General Safety
Requirements-Rule
35. Danger Notices)?

What if the portable   Lead to Electrical     Proper pre
tools are not          hazards                inspection and
provided with the                             handling of the
heavily insulated                             portable tools as
and adequately                                per IS rules to be
protected setup?                              maintained, and
(The Indian                                   pneumatic portable
electricity Rules,                            tools is recommended
1956-Chapter X                                for critical
Additional                                    operations
precautions to
beAdopted in mines
and oil-fields,
Rule-124. Portable
and transportable
machines)?

What if the            Electric Shock         Suitable protective
protective devices                            tools have to be
fail during the                               employed and before
operation?                                    using it has to be
                                              checked for
                                              eligibility at the
                                              time of issuing work
                                              permit.

What if the            Leads to mishaps       Standard color is
different lines and                           used to
circuits are                                  distinguished the
notdistinguished?                             different lines and
                                              circuits

What if the auto       Diesel generator       Frequent checking
main panel (AMF)       will not startup       has to be
fails?                 leads to various       established
                       issues related to
                       failure in
                       uninterrupted power
                       supply

What if the roof       Electric and fall      All roof trusses
trusses are not        hazard                 with purlins has to
earthed?                                      be earthed

What if the ELCB is    The faulty situation   Suitable rated ELCB
employed or not        is not identified      has to be provided
working?                                      and to inspect
                                              periodically.

What if the L.P.G      Chance of fire is      To be avoided and
lines are present      more                   isolated
near powerhouses?

What if the alerting   Leads to hazards       LOTO has to be
techniques like LOTO                          employed
is not followed?                              mandatorily.

What if the            Gloves fail to act     Periodical changing
electrically           as an insulator        of rubber gloves to
protected rubber                              be followed
gloves are not
changed
periodically?

What if the flame      Leads to fire or       Flame and dust proof
and dust proof light   failure of equipment   equipment has to be
fittings is not used                          employed at
in required areas?                            appropriate places.

What if the            Major mishap           Periodical bus bar
 interlocks in                                cleaning has to be
the bus bar fail?                             done


Check list Analysis:

The following is the chart prepared for the purpose the assessment of electrical safety system in the industry.
Table 4: Checklist for electrical safety analysis

ITEMS                                                     YES     NO

GENERAL

* Safety signs and tags used when necessary to warn       YES
employees about electrical hazards.

* Electrical sirens are used for specified places         YES
where much attention is needed

* Barricades used with safety signs when necessary to     YES
prevent or prohibit the employee access to work areas.

* Signalman need to warn when signs or barricades are     YES
not sufficient to prevent unauthorized access.

* Is electrical safety part of your staff induction?      YES

* Do all electrical equipment and cords have                      NO
inspection tags?

* Light switches easily locatable and in good             YES
working order?

* Is emergency lighting and exit lights adequate for      YES
the area?

* Is their ELCB is installed in circuits to facilitate    YES
at regular intervals?

* Are power switches and sockets are in good              YES
condition and labeled?

* Area is free from unexpected tripping of circuit        YES
breakers?

* Plugs are properly inserted all of the way into         YES
the power sockets?

* Appropriate use of power boards or extension leads?     YES

* Are extension cords a suitable length?                  YES

* Immediate removal of any frayed or damaged                      NO
electrical leads.

* Are flexible cords effectively anchored to              YES
equipment, plugs and sockets?

* Air vents and cooling fans in electrical equipment      YES
are free from blockage? Fans are quiet?

* Is faulty electrical equipment clearly marked and       YES
removed from service?

* Combustible material is not stored near electrical      YES
equipment?

* Do you report faulty electrical installations           YES
immediately?

* Work area free of any trip hazard from leads            YES
and cables?

* The fire protection system is employed on               YES
essential places

* The employed fire protection system has sufficient      YES
strength to handle the fire load at that point (As per
IS 2190 -Fire Extinguishers)

* While permitting a hand tool inside work area the       YES
fitness passport has to be issued

* All ELCB's to be not more than 30milli amps             YES

* Necessary checklists (e.g.: maintenance,                YES
housekeeping, checking of an apparatus etc.)
are maintained

* Workers must certified for their skills where ever              NO
required to perform and verified for their validity
of license(e.g.: worker certification grades like
B&C grades)

* Illumination on shop floor is as per IEC rule(Asper     YES
The Indian Electricity Rules, 1956- Chapter X-
Additional precautions to be Adopted in mines and
oil-fields 113. Lighting, communications and fire
precautions)?

* Operational and working distance has been                       NO
maintained (e.g.:panels and transformers)?

* Non sparking tools(e.g.:brass) are used in the          YES
LPG area

* Lightning arrestor are managed with suitable            YES
coverage? (Asper TheIndian Electricity Rules, 1956.
Chapter VIII-Overhead Lines, Under Ground Cables And
Generating Stations, Rule 92.

Qualified persons trained in and familiar with:

* Technically skilled person necessary to distinguish     YES
to manage the live parts from other parts of
electric equipment.

* Voltage determination.                                  YES

* Clearance distances that must be maintained.                    NO

* For specific hazards training has conducted has been            NO
specific to which the employee may be exposed to
risk during working.

Procedure provided for work on or near de-energized
parts:

* Written procedures specific to the equipment            YES
or worksite.

* De-energizing equipment.                                YES

* Application of locks and tags.                          YES

Working on or near exposed energized parts:

* All employees who work near to a hazard have been       YES
trained, and are aware of the practices.

* Only qualified employees work on energized parts.       YES

* Is an Overhead line are de-energized and grounded       YES
prior to working near them or other protective
measures used.

* Vehicle and mechanical operators understand that        YES
they must maintain a safe working distance.

* Insulating barriers are used and installed              YES
as required.

* Insulating mat is provided at all electrical            YES
equipment area

* Illumination is provided at all worksites to            YES
assure safe work.

* Protective shields and barriers provided to protect     YES
from the energized parts in confined space

* All conductive materials such as pipes, rods, etc.      YES
covered or insulated.

* Housekeeping performed when energized parts may         YES
not in contacted.

* Only qualified persons allowed defeating electrical     YES
lockout & tag out system must be followed work on
equipment.

Portable electric equipment such as cord-and-plugs,
including flexible cords:

* To avoid damage of cords avoid horse play with cords.   YES

* Not used to raise or lower equipment.                   YES

* Not fastened with staples or hung so as to damage       YES
insulation.

* Visually inspected before each use on each shift.       YES

* Defective items removed from service.                   YES

* Plugs and receptacles mate properly.                    YES

* Flexible grounding-type cords have a grounding          YES
conductor.

* Grounding plug not defeated.                            YES

* Adapters which interrupt grounding continuity not       YES
used.

* Approved equipment used for work during working                 NO
under conductive locations (e.g. wet locations, etc.).

* Is portable cable reels unwound fully before use?       YES

* Look at joints are properly secured after               YES
the connections

Test instruments and equipment:

* Used by qualified persons only.                         YES

* Visually inspected before use.                          YES

* Test instrument to be rated for the circuit which is    YES
to be tested and appropriate for the environment.

* Cabling of Electrical equipment ignite flammable or     YES
ignitable materials not used if present in the
worksite.

Safeguards For Personnel Protection:

* Protective equipment is used when there is exposure     YES
to potential electrical hazards.

* Are safety glasses or goggles used to protect eyes      YES
or where there is a sparks, danger of arcs, flashes
or flying objects?

* Approved gloves worn that are appropriate for           YES
the hazard present

* Are Insulated tools or handling equipment used while    YES
working in conductors?

* Is Insulated fuse, ELCB, handling equipment are         YES
used to remove or install fuses when terminals are
energized?

* Is non-conductive ropes and hand lines used near                NO
energized parts and are protected from moisture.

* Is Protective shields, barriers or insulating           YES
materials are used to protect employees during working
near exposed energized parts.


From the above analysis and reports it has been ranked low, medium, high the importance and attention needed to be taken.

Low:

** Roof trusses are not earthed

** Open wires and bare cables is present at few places

** Electrically protected rubber gloves are not changed periodically.

Medium:

** All transformer doors and fence earthing is missing at few places.

** Static discharge points are not provided near L.P.G yard and transformer yards.

** Ropes used near energized parts are conductive and are not protected from moisture.

** Workers under contractors are not ensured for their electrical operation certification.

High:

** L.P.G lines are near 11KV/440V substation.

Conclusion:

The concept which lies behind the selection of this current project is the Principle of Dominos philosophy. Unsafe actions and unsafe working conditions will pave the way for the injury and will even lead to the accidents. From the assessment of electrical safety practices with the application of the checklist analysis and what if analysis in the heavy engineering industry, the individual activities/ operations/ equipment's/ practices are going be assessed for the finding of the electrical hazards.

Initially the list of practices and points are logically and virtually analyzed and a chart is prepared necessary for the data collection to comply with the checklist and what if analysis. In future, the project will end with the findings of hazards, suggesting the recommendations and control measures of safe work practices associated with the electrical activities.

REFERENCES

[1.] Alex Albert, Matthew R. Hallowell, 2013. published a paper on the "Safety risk management for electrical transmission and distribution line construction"

[2.] Manuel Suarez-Cebador, Juan Carlos Rubio-Romero, Antonio Lopez-Arquillos, 2013. published a paper on the "Severity of electrical accidents in the construction industry in Spain"

[3.] Price, C.J., N.A. Snooke, S.D. Lewis, 2006. published a paper on the "A layered approach to automated electrical safety analysis in automotive environments".

[4.] Gheorghe Grigoras, Cecilia Barbulescu, 2013. published a paper on the "Human errors monitoring in electrical transmission networks based on a partitioning algorithm"

[5.] James, C., Cawley, Gerald T. Homce, 2003. published a paper on the paper" Occupational electrical injuries in the United States, 1992-1998,and recommendations for safety research"

[6.] Xinyan Huang, Yuji Nakamura, Forman A. Williams, 2013. published a paper on the paper" Ignition-to-spread transition of externally heated electrical wire".

(1) Ranganathan. K, (2) N. Nagarajan, (3) K. Mugundhan, (4) PSS. Srinivasan, (5) K. Visagavel, (6) D. Sakthivel

(1) Student, Department of Industrial Safety Engineering, Knowledge institute of technology, TamilNadu, India.

(2,3,4,5,6) Faculty of Mechanical Engineering, Knowledge Institute of Technology, Salem, Tamilnadu, India.

Received 25 April 2016; Accepted 28 May 2016; Available 5 June 2016

Address For Correspondence:

Ranganathan. K, 1Student, Department of Industrial Safety Engineering, Knowledge institute of technology, TamilNadu, India.

E-mail: rangaise@outlook.com
Table 1: Effects of electrical current in the human body

Current                    Reaction

Below 1milli ampere        Generally not observable

1milli ampere              Faint tingle

5milli ampere              Felt disturbing like shock, but no pain.

6-25milli ampere (women)   Muscle control loss and painful shock
                           occurs

9-30milli ampere           The freezing current lead to muscle
                           disturbing it causes to injury

50-150milli ampere         Extreme pain, respiratory arrest, serves
                           muscle reactions. Death is possible.

1000-4300milli ampere      Heart ceases from pumping action.
                           Occurrence of nerve damage and muscular
                           contraction.

10amperes                  Probably death, Cardiac arrest, severe
                           burns.
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Author:Ranganathan, K.; Nagarajan, N.; Mugundhan, K.; Srinivasan, PSS; Visagavel, K.; Sakthivel, D.
Publication:Advances in Natural and Applied Sciences
Date:Jun 15, 2016
Words:2798
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