SAN FRANCISCO (KCBS) – Smoking anything other than medically-prescribed marijuana at San Francisco street fairs, festivals and other outdoor events held on city property would be banned under new legislation before the Board of Supervisors. Supervisor Eric Mar said he introduced the proposal because of the health impacts of secondhand smoke when people light up in public. “It’s widely known that secondhand smoke is responsible for as many as 73,000 deaths among non-smokers each year in the United States, and there is no safe level of exposure,” he said.