SAN FRANCISCO (KCBS)— The San Francisco Fire Department evacuated Boudin Bakery in response to what they thought was a possible hazardous materials situation at Fisherman’s Wharf Friday morning, but turned out to be pepper spray.

San Francisco Fire Department spokeswoman Mindy Talmadge said it happened around at 10:20 a.m. at the restaurant on Jefferson Street.

READ MORE: 12-Year-Old Antioch Girl Shot Dead Inside Home; Suspect At Large

She said people were coughing in the Bakery, so crews decided to evacuate it.

“Somebody actually discharged pepper spray in the establishment.” Talmadge said. It wasn’t clear who discharged the substance, but 11 people were treated on scene and refused transport to the hospital.

READ MORE: Wildfire Season: Lafayette City Council To Hold Special Meeting On Wildfire Response

When it initially occurred, a hazmat team brought in CGI monitors to see if anything registered, according to Talmadge.

“It just measures the air content and if anything poisonous is in the air, it registers that in the parts per million.”

CGI stands for Combustible Gas Indicator, according to http://www.fireengineering.com.

MORE NEWS: Pittsburg Drive-By Shootings Caught On Camera; Police Seek Suspects

TM and © Copyright 2015 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2015 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. Bay City News Service contributed to this report.