Electricity Initiated Fire Hazard

The object of the study is to examine efficacy of the prevailing safety regulations with regard to easing out incidences of electricity initiated fire hazard in electrical installations, and effectiveness of enforcing mechanism to curb thereof... - Ritabrata Sanyal

The reported news in ‘ The Telegraph ‘ on 22nd March 2016 about an incidence of fire, thought to be an electricity initiated fire, ravaging the heritage Zoology Laboratory of the Ballygunge Science College of the Calcutta University entailing property loss of about rupees 2 cr., besides irretrievable work of research scholars and priceless museum specimens of nearly extinct animals came under public domain.

Following that, on 29th March 2016, there has been an incidence of fire, thought to be a fire initiated by short circuit in LT installation, in a newly constructed commercial complex at Salt Lake, Kolkata in sector V – requiring more than one hour to put it out. The loss of property here also is reportedly significant.

On April 7, 2016, an electricity initiated fire from AC machine broke out in a Central Govt. estab-lishment situated at Salt Lake, Kolkata in sector V points toward maintenance lapse calling for all time stricter vigilance cover as the Regulations of CEA contemplate (Anandabazar Patrika, 8th April’16).

The above news have saddened every one because of consequential damage of such enormity – and obviously throws open the door for relooking the sufficiency of the prevailing Safety Regulations of the Central Electricity Authority with regard to restricting / mitigating electrically initiated fire in domestic and commercial premises.

The picture of electrical wiring in the University building, as appeared in the above stated edition of ‘The Telegraph’, distinctly speaks of weakness in the maintenance vigilance thereof.

The object of the study is to examine efficacy of the prevailing safety regulations – with regard to easing out incidences of electricity initiated fire hazard in electrical installations, and effectiveness of enforcing mechanism to curb thereof.

To understand the basic essentials leading to triggering of fire from electricity causes, primarily, in short circuit, earth fault and overload situations, the probable factors correspond to ignition of fire need to be scanned. The factors are :

1) Carbonization of insulation
2) Short circuit / earth fault / gross overload
3) Excessive ‘ohmic’ heating (‘hot-spot’ situation)
4) Inconsistently performing installed equipment.

It is an accepted fact that the risk probability, under unfavourable operating circumstances, on account of carbonization of wire /cable insulation, primarily PVC, in installations using substandard insulated wires /cables is distinctly high. Despite that, in reality, high initial cost of PVC insulated wire / cable conforming to IS specifications, and lack of awareness about the potential hazard on usage of substandard wire / cable generally prompt one to use it in LV /MV installations.

The study, carried out on the subject of cable-insulation failures by different research organizations, has since identified the causes of breakdown as carbonization of insulation and, as a result, ignition of PVC insulation of wires / cables occurs. The factors are: gross overloading of wire / cable, localized heating due to conductor-strand breakage or loose terminal connection.

The poor insulation quality of substandard wires / cables, in the above stated circumstances, creates a semi-conductive path in insulation for leakage current even at 230 V and that ends up in electric arcing. The present trend of using PVC insulated wires / cables in installations without paying any heed to their quality corresponding to the locations of use makes the situation critical since PVC insulation, on exposure to temperature beyond the allowable limit, hastens its failure.

As to short circuit, the sudden flow of a very high magnitude of current through a very low resistance path is the manifestation of short circuit in an installation. Conductor to conductor contact in such an unwarranted situation creates a low resistance conducting path for the fault current. Sparking may appear as the conductors go apart. The arc, so formed, may lead to ignition of combustible materials in close vicinity.

The similar situation is also developed on occurrence of earth fault in an installation connected to earthed system of supply. Here, a very high amount of earth fault current flows through the faulty circuit to earth for ultimate dissipation. The contact of live conductor with earth conductor / earthed non-current carrying fittings in the installation constitutes the earth -fault path. Electric arcing may also appear on such a situation.

With regard to excessive heating under hot-sport situations, loose connection in the electrical installation is the real offender since the situation creates a localized high resistance path for the current and results in overheating. Continuance of the abnormality for a short time, because of high ohmic resistance, may ultimately show up as glowing connection and may lead to ignition of nearby combustible materials.

Inconsistently performing installed equipments may also create situation conducive to fire-risk.

Analysis of the attendant circumstances leading to electric fire with reference to Safety Regulations of CEA

Since, in reality, the use of substandard installation materials and apparatus has been rampant, watchfulness against their use in the installations is the desired administrative step. Here, the role of the owner of the installation is pertinent, since he himself is affected in consequence of accident in his electrical set-up. The role of the Licensed Electrical Contractor and the Supplier is equally vital (regulations 29(1) & 33(1)). The knowledgeable circle believes that, very often, their relaxed approach in discharging the assigned obligations under the Regulations of CEA, in most cases, leads to electricity initiated fire on consumers’ premises.

The matters regarding general safety requirements in electrical installations have been the subject of regulation (12) of the Central Electricity Authority (Measures relating to Safety and Electric Supply) Regulations, 2010. The provision makes specific reference to the matters pertinent to electrical safety during construction of electrical installation and safe use of electricity thereafter. The stipulation is also critical about the quality, current and voltage ratings of the installation materials corresponding to locations of their use.

The distinctive qualities of installation materials for the installations have been laid down in regulation 33(6). The provision lays emphasis on the use of insulating materials suitable for the proposed use and also maintenance of their qualities on all working conditions, such as temperature and moisture. The cable insulation, it is felt, also comes under its purview.

It is felt that, to have an installation operating consistently without any reasonable threat of malfunction therein, the selection of installed materials and apparatus conforming the relevant specifications of IS code is the prerequisite. It is evident, therefore, the fire- risk- factor due to carbonization insulation of wires / cables would appreciably come down upon use of installation materials without making any compromise to their quality.

As regards short circuit or like situations in electrical installations, inadequacy of the protective arrangements therein comes to the fore. The CEA Regulations, with an eye to plug up such eventuality, involve the Supplier in the matter and recognize the Supplier’s satisfaction as to right compliance with laid down safety requirements by the owner of the installation prior to effecting the supply (regulation 33) . The measure proves effective in detecting inconsistency in the installations awaiting for the supply.

On top of that, in 2015 by an amendment of regulation (43), electrical installations, based on the notified voltage, are sub-divided into two categories. The installations, having voltage up to and including the notified one, are put under self-certified category and that above the notified voltage are placed under the inspection ambit of the Electrical Inspector. This means that the Electrical Inspector would only be competent to accord pre-energization approval of the installations of the voltage class above the notified voltage. However, for installations under self-certified category, the owner’s certificate in lieu of approval of Electrical Inspector is considered adequate for the purpose enjoying the supply of electricity from the Supplier.

As to hot- spot situations, one is inclined to put blame on the Electrical Contractor for poor execution of installation work.

It is evident, therefore, that the 2010-Regulations of CEA, as amended up to date, not only ensure regulatory watchfulness on maintenance of protective qualities in installations but also on safe use of electricity.

The Regulations are critical also about the role of the persons, on whom inspection and testing for electrically safe installation rest .

Safety Regulations of the Central Electricity Authority

The Regulations, concerning measures relating to safety and electric supply, framed by the Central Electricity Authority (CEA) pursuant to the Electricity Act, 2003, took effect in 2010 vide Notification No. CEI/1/59/CEA/EI dated the 20th September, 2010. The regulations hold pertinence to ensuring electrical safety, not during erection stage but in-service situations also, and make specific reference to the role of the enforcing mechanism to carry into effect of the safety provisions in right spirit.

Understandably, there is scope for viewing the reported incidences of electric initiated fire as an effect of deficient upkeep of the installations, primarily by owners. But, the role of the supplier or the designated officials responsible for over-seeing safe maintenance thereof as per the said regulations needs scanning since the matters relating to electrical safety during their construction, installation, protection, operation and maintenance come under the jurisdiction of regulation 12 of the 2010 – Regulations of CEA .

Generally, an electrical set-up, be it at domestic or commercial premises, before being ready to receive the supply, passes through the following procedural- sequences :

  1. Design of installation by keeping with a view to the mandatory protective features under the said regulations along with the recommendations of relevant IS standards .
    2. Selection of installation materials and apparatus without making compromise to their qualities, both in respect of specifications and rating, and also their suitability for the operating environment [regulation 12(3)] .
    3. Entrusting the State Govt. Licensed Electrical Contractor to carry out the installation work under direct supervision of a person holding the competency certificate for the type of work undertaken (regulation 29).
    4. Pre- energizing inspection and testing of the prospecting consumer’s installation by the Supplier before connecting it with his system of supply has been made obligatory (regulation 33(1)).
    5. Mandatory inspection of installations of voltage-class exceeding the notified voltage by the Electrical Inspector prior to commencement of the supply [regulation 43(2)].
    6. Self- certification by the owner of installation of notified voltage or below, awaiting for the supply [regulation 43(1)].

Regarding safe maintenance of the installation in – service situation, regulation 30(2) is very specific. The provision vests the responsibility of periodical testing and inspection thereof either in the Electrical Inspector or in the owner /consumer / supplier in respect of electrical installations based on the notified voltage, meaning the notified supply voltage.

Hence, installations of voltage above the notified voltage and that equal to or below are put under separate slot. Accordingly, installations above the notified voltage come under the inspection ambit of the Electrical Inspector [regulation 30(3)] and the rest are put under self-certified cover of the owner /consumer / supplier [regulation 30(2)].

It is confusing that regulation 30(1) speaks of involving either the Electrical Inspector or the Supplier, as may directed by the State Govt., for periodical inspections and testing of electrical installations. The provision is silent about legitimizing the owner’s certification as the testimony to safe up-keep of his electrical set-up.

Visualizing escapist mind-set of owners of the installations in generality, the Central Electricity Authority amended regulations 30 (2) to (5) of the 2010-Regulations in 2015 – with a view to making the periodic inspection of electrical installations more meaningful.

By a substitution in regulation 5 ibid, a basic change in the compliance mechanism at pre-energizing stage or during periodical inspection of installations was brought about by authorizing Chartered Electrical Safety Engineers, having requisite qualification and experience as of Electrical Safety Officer, to aid suppliers or consumers in the matters of testing, and observance of safety regulations (regulation 5A).

To make the arrangement rationally workable, CEA, based on the notified voltage, divides installations of voltages above 650V into two groups. However, no mention has been made with regard to periodical inspection coverage of installations below 650V. It is reasonably presumed that the self-certification by the owner the installation would prevail.

Regardless of installations of voltage equal to and below the notified voltage and having load demand of above 250 kW, the regulation 5(4) IBID makes it incumbent upon the owner thereof to appoint an Electrical Safety Officer to look into adherence of safety provisions.

But, the facts remains that the owner of installation having load demand of above 250 kW at or below the notified voltage (necessarily of voltage above 650 V) may not have any duly qualified engineer for appointment as electrical safety officer.

The unworkable obligation needs to be attended to with reference to ground reality to make the provision effective in achieving the desired objective of electrical safety. It is felt that, a prudent remedy to the said limitation would be to allow the owner of the installation to hire the service of a Chartered Electrical Safety Engineer form a panel, to be notified by the Sate Govt., for the purpose of inspection and testing of his installation. The matter calls for consideration of CEA.

The administering mechanism under the CEA Regulations, making Electrical Inspector, Electrical Safety Officer, Inspecting Officer or Supplier responsible for overseeing right implementation of electrical safety regulations both during and after commissioning of the installation, will ensure vigilance cover for electrically safe installation.

Therefore, one is inclined to take the view that, for identification of the weakness in the electrical installations, the periodical inspection of the electrical set-ups at a regular interval bears great relevance. The knowledgeable circle believes that timely detection of inconsistencies in the electrical installation would keep down the incidences of electric fire to a substantial extent.

Therefore, periodical inspection and testing of the installations by a duly qualified engineer at an interval of at least once in a year, as set under regulation 5 ibid, it is felt, is the right remedy.

However, for installations of the multi- storeyed buildings and important residential and commercial complexes, because of complexity of the electrical set-up both in terms of load demand and utility voltage, the right compliance with the safety stipulations should be put mandatorily under the superintending – cover of the Electrical Inspector, who gets a copy of the self-certified periodical inspection report from the owner of the installation.

Again, the submission of self–certified report in terms of regulation 30(3) ibid by the owners of the installation equal to or below the notified voltage without ratification of the information furnished therein by the Chartered Electrical Safety Engineer would, it is believed, defeat the very objective of achieving electrical safety since, in reality, the owners may not have the right competence as the provision of the regulation 30 contemplates.

Conclusion

There is no denying that regulatory-appropriateness is a necessity. The administering mechanism under the said Regulations, however, has not shown enough activism to prevent incidences of electric fire, even in important establishments as mentioned above.

The weakness needs to be set right to make the mechanism appropriately responsive with regard to consumers’ observance of safety measures, particularly, under in-service situations.

Recommendations

In view of the facts as stated above, it is felt that the inspection report in form I, II & III of Schedule IV, as the case may be, under regulation 30(3) of the CEA (Measures Relating to Safety and Electric Supply) Amendment Regulations, 2015 be considered for revision to bring in the ratification of the information contained in the owner’s self – certified report by Chartered Electrical Safety Engineer obligatory, since the owner may not have the right competence to carry out inspection and testing of his installation as the regulations contemplate.

Periodical inspection report of important installations with considerable load demand under owners’ self-certification cover be put through subsequent scrutiny by the Electrical Inspector to exercise closer watchfulness on safe maintenance thereof, since the owners’ maintenance lapse, as it appears, had been the prime initiator of electrical accidents leading to electric fire.

The appropriate government should be empowered to prepare a panel of Chartered Electrical Safety Engineers of requisite qualifications and experience to aid the owner of the installation falling under self-certified category to carry out inspection and testing for ratification of the owner’s Inspection Report in terms of regulation 30(3) of the CEA (Measures Relating to Safety and Electric Supply) Amendment Regulations, 2015.


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