sule 66fact, in July 1966, when Rule 66 was adopted, some 600 tons per day of organic solvents were being discharged into the County's atmosphere, representing one-fifth of the total organicHhway Code Rule 66. Hhway Code > Rules for cyclists (rules 59 to 82) > Hhway Code Rule 66. You should. avoid any actions that could reduce your control of your cycle; be considerate