Assistant Deputy Fire Chief Dale Carnes, based out at SFO's Station Three, was on scene out at Runway 2-8 Left after the plane crashed.
"We had the fire completely out and were in overhaul stage and we were made aware of the potential of phosphorus being on board," said Carnes.
According to one source at least 45 pounds of yellow phosphorus was in the planes cargo hold.
Thursday, a spokesman for the NTSB sent an email that read in part: "The FAA's ash security and hazmat division determined the shipment was actually yellow phosphor, which is not classified as hazardous material."
Deputy Chief Carnes disagreed with that assessment.
"Its a hazardous material; highly flammable," said Carnes. "Not something you want to get on you or ingest."
At 2:51 p.m., three and a half hours after the crash, the San Francisco Fire Department sent out an internal email -- obtained by KTVU -- to all officers.
It reads: "All units who responded to plane crash, decontaminate all turnouts and turn in for cleaning."
All our personnel were wearing their personal protective equipment or what we call PPE. They were all wearing self-contained breathing apparatus, explained Carnes. We take decon precautions on every fire.
THE CDC'S website says yellow or white phosphorus is often used in fertilizers or matches. It can rapidly react with oxygen, catching fire at temperatures 10 degrees above room temperature.
"We dealt with an engine fire and we did have some extension into the aircraft," said Carnes.
When asked if phosphorous could lead to worsening conditions, Carnes replied in the affirmative.
"Absolutely. To my knowledge, we never saw any indications of that," said Carnes.
A source close to the investigation said Senator Dianne Feinstein's office notified city officials about the yellow phosphorus.
Thursday, a spokesperson for Feinstein's office said the senator was briefed about the cargo by the FAA just hours after the crash and that she did contact city officials including Mayor Ed Lee.
The NTSB said it does not know where the phosphorus was going or who sent it.
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