Fire Accidents, Before & After

What are the common causes and factors that lead to electrical accidents in buildings and how can they be prevented?

Electrical faults can cause dangerous voltages, high-fault currents, and explosions, damage to equipment and property, personal injury, and leads to fire accidents as well. A likely cause for most of the electrical accident are insulation failures, SC, Mal function, surges, delay in fault isolation and having a poor quality of components used

We should find a root cause to understand why these failures are happening again & again so that to mitigate the same in future. If we try to understand more about Insulation failure

It is an Electrical breakdown or dielectric breakdown is what we can precisely say and It happens when voltage applied across it exceed the breakdown voltage. This results in the insulator becoming electrically conductive. Electrical breakdown may be a momentary event (as in an electrostatic discharge), or may lead to a continuous arc if protective devices does not trigger. It is just because of Insulation deterioration which is one of the primary causes for insulation failure. The Insulation deterioration is nothing but a dielectric contamination which may be due to temperature cycling, excessive overloads, excessive voltage stress due to overvoltage, and advance aging.

Similarly Short circuit is another major contributor towards fire accident. The Insulation failures due to over voltages, which in turn allow current to flow in undetermined path to create short circuit in the circuit. There are more possibilities like wrong installation, bypassing commissioning process, Pests: Animals like mice, rats and squirrels and their innocent contact with the live conductors and strangely most common mistakes is forget to take out our tools, loose hardware etc., after repair/maintenance.

There are more technical causes like external surges, Internal surges due to switching of thyristors, server switching, chiller operation etc., which are hardly audited post-accident scenes.

Fault isolation at rapid speed would not have happened.

This happens many a times as the protection relays are set to the value of actual current
Wrong selection of breakers, discriminate factor while breaker selection etc., would lead to the Breaker to not function at a right time

Using faulty components are also leads to the faulty operation resulted in fire accidents

BIS marking, CE approved, UL listed are neglected during procurement & installation
CE marking is a certification mark that indicates conformity with health, safety, and environmental protection standards for products sold
Many of the products which are used in the industry are not even certified by BIS as ISI mark
Lift cycles of the components are not pre-evaluated and monitored post installation

Safety practices are missing

As we all are aware, the Electrical faults are unpredictable in nature
The safety measures should be preached and practiced at all times by all concerned as a normal routine duty
Rubber gauntlets, gloves, mats, boots and galoshes, insulated platforms, insulated stools, safety belts, hand lamps, tower wagons etc., shall be used while working or during maintenance
Adequate illumination under emergency power is must to fight against any accidents
Not to have an outdoor maintenance activity during lightning storm days
Not to roll up shirt sleeves while working
Keep fire extinguishers, first aid boxes, stretchers, aromatic spirits of ammonia, , handy for better handling of post-accident scenarios
Not to use copper wire as a replacement for fuse wire
Not to bring naked light near battery

There are ample number of major fire accidents which had become by then talk of the town like Uphaar cinema hall, Carlton tower, The 2013 Kolkata market, AMRI hospital

Most of the electrical accidents are generally due to carelessness and result in fall, fire, or electrical shock.

Let us understand the basic of fire

Fire is one of the greatest things admired and feared by all living things on earth
Fire is a chemical reaction happens in combustible material in contact with oxygen to give heat and flame. In simple, heat, oxygen and combustion material together only can cause fire
Fire is classified as Class A, B, C, D and E.
A to D class of fire is mainly due to combustion materials like solid fuels, liquid fuels, gaseous substance and metal fires
E class fire is contributed by electrical system like insulation failures, SC, Mal function, surges and delay in fault isolation apart from having a poor quality components
10 minutes of continues fire can raise the temperature to 700 degree C

PREVENTION from anticipated cause of accidents

Use reliable components (I don’t say certified because ISI certified materials were also found faulty in few instances)
Have though commissioning process
Conduct safety practice on regular basis
Use current technology to assist your maintenance team as an intelligent model for example Nitrogen based fire arrestor for the Transformers, fire tubes for the panels, temperature sensors for the busducts and rising mains etc.,