Every person, company or corporation operating street railway passenger cars within the limits of the City and County of San Francisco in which passengers are carried shall thoroughly wash each car, when so operated, at least once a week, and shall also carefully sweep and clean each of said cars daily.
Whenever required in writing by the Department of Public Health, all persons, companies or corporations operating street railway passenger cars within the limits of said city and county shall thoroughly disinfect each street railway passenger car so operated by spraying said cars with an efficient disinfectant.