HRS §339-12
Releasing balloons is banned
This law bans releasing balloons filled with lighter-than-air gas, with a few exceptions. If you break the rule, you can be fined. Releasing several balloons at once counts as one violation.
everyone
The statute, as written — 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.
LawTrove is not legal advice. The summary above is a computer-generated restatement — the authoritative text is the official version linked above.