California Code, Business and Professions Code - BPC § 22200

No bag made of plastic material of an average gauge thinner than 0.001 inch which is large enough to fit over a child's head shall be used by any business establishment as a container for products delivered to purchasers, or by any other business establishment to package articles delivered to customers or other persons doing business with the establishment, or, after January 1, 1988, shall be directly sold, delivered, or given to any business establishment located in the State of California by any manufacturer, supplier, or distributor after January 1, 1988, unless there is printed upon such bag, or upon a gummed label which is securely attached to such bag, in clear legible type the following:  “CAUTION--KEEP AWAY FROM SMALL CHILDREN. THE THIN FILM MAY CLING TO NOSE AND MOUTH AND PREVENT BREATHING,” or a similar warning that the bag is dangerous to small children.This section shall not apply to those plastic bags which are used exclusively for industrial purposes.