As much as 100 gallons of hydrochloric acid spilled at Communications and Power Industries (CPI) Wednesday morning, Palo Alto Emegency Manager Barbara Cimino said late Thursday, tripling the originally estimated size of the spill.
Fire Marshal Dan Firth, who was not on the scene, said Thursday afternoon that more than 20 gallons spilled.
Cimino said 10 to 20 gallons spilled outside and 50 to 80 gallons were released within the building on Hansen Way.
No one was injured or exposed to the corrosive chemical and it was cleaned up by mid-afternoon, Cimino said.
Firth said CPI complied with the requirement to inform the Fire Department immediately.
The incident occurred around 9:15 a.m. when a hydrochloric acid supplier was filing a chemical storage tank, CPI spokeswoman Amanda Mogin said.
A gauge monitoring the amount of liquid in the tank malfunctioned, Mogin said. Employees noticed the tank was taking longer than usual to fill and cut-off the flow, averting a potentially larger spill, Mogin said.
About 10 gallons of hydrochloric acid, a usually clear chemical with an acrid odor, flowed out of the building through a vent, Firth said. Another 10 to 20 gallons pooled within the building, he said.
Firefighters arrived "very, very quickly" and cleaned up the outdoor spill within two hours, Mogin said.
Bicarbonate of soda, or baking soda, is used to neutralize the acid, which can then be vacuumed up, Firth said.
Mogin said CPI plans to replace the gauge and launch an investigation into the mishap.
Firth said the company has five days to submit a detailed report to the city. Any potential penalty will depend on information in that report.
All accidents do not result in fines, he said.
Cimino said the Fire Department is conducting an investigation.
CPI uses hydrochloric acid to clean materials used to manufacture vacuum electron devices, Mogin said.