Legally concealed firearms are included in this ban. 

Via SF Bay News: 

The Santa Clara County Board of Supervisors voted unanimously to preliminarily adopt an ordinance regulating firearms and ammunition on county property at their meeting Tuesday.

The ordinance adds a new chapter and modifies an existing one in order to “prohibit the possession, sale or discharge of firearms and the possession or sale of ammunition on county property.”

County Counsel James Williams introduced the proposed ordinance, which he and his staff compiled to model ordinances passed by other California cities and counties.

Locally, this ordinance’s language and structure echoed that of San Mateo and Alameda counties’ firearms ordinances, Williams said.

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