March is ‘heat-transfer info’ month

CEBU, PHILIPPINES — FO1 Wendell Villanueva, Bureau of Fire Protection 7 public information officer, mentioned that fire starts in many ways. “Some are slow, some fast. These happen in different stages.”

The incipient stage has no visible smoke or flame yet. The smoldering stage shows smoke but without flame. The flame stage, as the name suggests, has both smoke and flame. While the heat stage has this uncontrolled spread of superheated fire. “Fire spread in four ways,” he added as he enumerated heat transfer by radiation, heat transfer by conduction, by convection and direct heat transfer.

Heat transfer by radiation involves the stages of emission, absorption and transmission of heat or energy. It involves the thermal process whereby atmospheric circulation is maintained through the upward or downward transfer of air masses of different temperature. Heat by conduction is the transmission of heat from one body to another. It is the transfer of heat from one molecule to another molecule. Heat transfer by convection is the diffusion of heat in liquid or gas form through the motion of its parts, while direct heat transfer is the transfer of heat from one body to another through direct flame contact.

“That’s what we would want to avoid. Heat transfer by radiation, so automatic ang cooling down of exposures.” Another very good point raised is the misnomer in the reporting of fire incidents. “Mao sad nay lisod if wrong or inappropriate ang termino gamiton sa reporting, imbis makatabang og pasabot, makamugna hinoon og confusion,” he expressed.

An often misused and misunderstood phrase in reports is faulting electrical wiring. “If there is actually faulty wiring, there would have been no electric power from the very start when you switch on the circuit breaker or the main service protective equipment,” he explained.

So what actually happens? According to Villanueva, “the wires or circuit becomes overloaded because of the increase in the load the circuit carries without changing the size of the wires. The subsequent effect will be weakening of the insulation of the wires due to overheating in the circuit caused by the additional load.”#

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