Maximum flow rates have historically been set by the Appliance Efficiency Regulations, and all faucets and showerheads sold in California must meet these standards. California’s Title 20 Appliance Efficiency Regulations contain the maximum flow rate for showerheads and lavatory and kitchen faucets. Current flow requirements contained in the Title 24 Part 11 CALGreen Code set more efficiency levels. Installations of showerheads and faucets are mandatory under the CALGreen Code.