TORRANCE (CBSLA.com) — Community activists in Torrance took on ExxonMobil Friday night, days after a refinery explosion sent dust into the air and ash onto the ground that has raised health concerns for locals.

Demanding answers during a townhall meeting with company officials, dozens of locals say their homes and cars were coated with dust after Wednesday’s blast, which was strong enough to register as a magnitude 1.7 earthquake.

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(credit: Ken Koller/CBS)

(credit: Ken Koller/CBS)

Workers activated the facility’s flare system to burn off extra fuel, sending flames shooting hundreds of feet into the sky.

Four contractors suffered minor injuries.

The explosion also sent ash raining down onto neighborhoods below.

ExxonMobil maintains the dust is not dangerous. But residents say they’re not buying it.

“The only thing I hear here is your promise: ‘We care, we care.’ But I can’t see anything,” one community activist said.

“It’s not just earth and dust. There are elements to it that pose serious health concerns,” another said.

“Standing here as a parent this is very scary to me,” one woman added.

Company officials describe the substance as a “catalyst” used in the refining process.

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“It’s just like the dust you might find in your yard – not good to breathe, but nonetheless not hazardous in itself,” said refinery manager Brian Ablett.

ExxonMobil says it took multiple samples of the dust – along with government agencies – and all tested harmless.

Residents are skeptical, and also voiced concern the company did not do more to notify them of the explosion.

“We had breathed everything in that we were going to breathe in, and no siren at all. No warning,” one woman said.

ExxonMobil officials say they view the explosion as a wake-up call and plan to look into the ways they notify the public of emergencies.

Officials still don’t know what caused the explosion and they could not give a timetable on the investigation.

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