Haw. Rev. Stat. § 342B-5: Effect of laws, ordinances, and rules.

(a) All laws, ordinances, and rules inconsistent with this chapter shall be void and of no effect.

(b) Any county may adopt ordinances and rules governing any matter relating to air pollutant and air pollution control which is not governed by a rule of the department adopted pursuant to this chapter; provided that any county ordinance or rule relating to air pollution control shall be void and of no effect as to any matter regulated by a rule of the department upon the adoption thereof.