Mumbai 04 Feb 2022: The fire in 60 storeyed Avighna Park is from video doorbell, later spread to other parts. 

Mumbai October 25, 2022: A fire broke out in Vasai godown while Thane reported five different incidents of fire and another fire broke out in a Goregaon building.

Noida Jun 18, 2021: A major fire broke out at the office of the Noida Metro Rail Corporation in Sector 29, Noida on Friday afternoon due to an electrical short circuit.

Mangalore Jun 24, 2022: Fire incident at Mangalore showroom due to short circuit, says EV maker Okinawa.

Lots of incident happened PAN India, short-circuit is most common cause of blaze in buildings. Ashwini Bhide, additional municipal commissioner of the BMC informed the standing committee, “There is no mechanism for having societies conduct electrical audits. We are in communication with the state government to develop a regulatory mechanism for the same. We are also reviewing fire safety in hospitals and in the malls of the city.”

Bhide added, “In case of high-rises also we have been conducting fire drills and inspections regularly and taking all appropriate steps to ensure there is zero-tolerance for fire safety,” an officer said.

According to BMC officials, the MFB in the past three months have conducted fire drills at 52 high-rises and inspected 1,526 buildings in the past 20 months. Notices have been issued to 327 buildings, while 78 buildings have complied with violations, 109 are in the stage of compliance and prosecution against three housing societies is under process.

Further, the BMC’s standing committee on Wednesday also cleared a proposal of ₹3.15 crore for the procurement of 24 fire bikes for the city. According to BMC officials, the fire bikes will help firefighting in congested areas like chawls and slums. These fire bikes will be added to the fire-fighting fleet of the MFB.

FORMER MUNICIPAL commissioner Praveen Pardeshi, also the head of technical committee on Safety Manual to respond to man-made disasters, said on Monday that nearly 70 per cent of the fire incidents in Mumbai take place due to electrical short circuits. He was speaking at a panel discussion ‘Electrical Safety is non-Negotiable’ in the city.

“We have found that 69 per cent of the fire incidents reported in Mumbai happened mainly due to the failure of electrical installation. The second highest reason being domestic gas cylinder leakages, which is just 2 per cent. So, the numbers clearly state that if electric installations at residential buildings could be routinely checked and inspected, we could prevent 70 per cent of the fire incidents in Mumbai,” said Pardeshi.

An electrical system can deliver energy to a very small location, raising the temperature and causing a fire. Some appliances heat up by design, and the heat needs to be controlled.

Hazards

Short Circuit – Generally the result of two conductors touching when they should not touch. Can result in very high currents, overheating, arcing, smoke, fire, more short circuiting. Protection includes insulation of conductors, fuses and circuit breakers, substantial enclosures.

Loose Connections – Will generate heat as current is run through them. This can result in insulation failure, arcing etc. Protective measures include workmanship standards, inspection, training, infrared inspection of systems in use.

Overload – Can lead to insulation failure, shorting, arcing, fire. Prevention by designing with consideration of worst-case loads, thermal environment, nearby conductors and insulation type. Tables in NEC. Fuses and CBs to remove currents above design limits.

Arcing – Localized extreme heating of conductors resulting in plasma (arc) and incandescent metal particles (sparks). Prevented by keeping conductors apart with insulation or spacing.

Ignition of flammable vapors and gasses – will be covered in another talk. Fires caused by lightning will also be part of another talk.

Mitigations

Fuses – One-time current limiting devices made to open the circuit if the current exceeds a specified limit for a specified time. Fuses can be slow-blow or quick-acting.

Circuit Breakers – Re-settable current limiting devices. Most are dual-action that can trip on instantaneous overload or a longer, but lower, overload. Also carry an interrupt rating – how much current they can safety interrupt. Some larger breakers have adjustable time delays to help coordinate with other breakers.

Thermal Cut-outs and thermostats – Provide circuit interruption (either temporary or permanent) if the temperature gets too high.

Engineering Analysis – An electrical distribution system should be designed not only for normal conditions but for emergency, overloaded, conditions. A Load Study tells the designer how much power is needed at each location and how the system will provide it. A fusing coordination analysis shows what will happen in the event of an overload at any point in the system. The NEC requires these and refers to the IEEE “color book series” for details on how to do the analyses.

Grounding – Important not only because it keeps all exposed parts of the system at about the same potential to prevent electrocution hazards, it also provides a low-impedance path capable of tripping a breaker if a fault current occurs.

Arc-fault interrupter – The NEC now requires Arc-Fault Circuit Interrupters (AFCI) for circuits in bedrooms. These devices monitor the line for the RF noise characteristic of arcing (even low-power arcing).

Appliance and Equipment design – UL requirements for specific appliances (like coffee makers) include safety requirements like thermal cut-outs and types of wire allowable. Other requirements are also called out like accessibility (vent holes have to be small enough to prevent access to hazardous voltages by a standardized finger probe).

Component Standards – Component failure is reduced by compliance with UL standards for electrical parts (like UL 1699 for AFCIs).

The Maharashtra Fire Services of Government of Maharashtra is insisting to install an IOT BASED MICRO CONTROLLER DEVICE, claimed to be offering multiple safety measures as per IS732.

Note: The Circular CEI 2021/P.No.114/Energy-5, Energy Department, Government of Maharashtra is included in Annex A.

• (This "Fire Safety Blogs" Published in December 2023  Edition)