By CBSLA Staff

UPLAND (CBSLA) — The soldering of copper pipes in a bathroom sparked the devastating fire that damaged 51 apartment units in Upland earlier this month, officials announced this week.

(credit: CBS)

A three-alarm fire ripped through an apartment complex in the 900 block of West 7th Street on May 4, scorching at least 51 units and displacing dozens of families. One firefighter was hospitalized with a heat-related injury, and more than one pet died in the flames.

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According to San Bernardino County fire Battalion Chief Mike McClintock, the cause of the fire started due to copper pipes being soldered in a second-story apartment bathroom.

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“After soldering pipes in a bathroom, multiple residents and the repair person smelled and saw smoke from the attic space,” McClintock’s statement said. “They immediately called 911 and located a nearby fire extinguisher, attempting to suppress the fire. Unfortunately, the fire had already extended up the wall and into the attic space.”

Windy conditions fanned the flames, which spread through the building’s insulation, exposed lumber, and other combustible items in the common attic space, McClintock said.

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Blazes caused by torches used by plumbers to solder metal pipes are actually among the top 10 causes of residential fires every year, according to the National Fire Prevention Association. McClintock says plumbers and repair workers should always use flame protector cloth or steel plates to protect flammable material near soldering sites, keep a bucket of water, spray can or wet rag nearby, and have a working and recently-inspected fire extinguisher on hand.