Haw. Rev. Stat. § 339-12: Intentional release of balloons; prohibition.

(a) No person or entity shall intentionally release, organize the release of, or otherwise cause the release of a balloon inflated with a gas that is lighter than air, except for:

(1) A balloon released for scientific or meteorological purposes, on behalf of a governmental agency or pursuant to a governmental contract;

(2) A hot air balloon that is recovered after launching; or

(3) A balloon that is released and remains indoors.

(b) Any person or entity who violates this section shall be subject to a civil penalty of no more than $500 for each offense. For the purposes of this section, the release of multiple balloons at one time shall be considered a single offense.