US lawMinnesotaRegulationsDEPARTMENT OF HEALTHChapter 4620 — CHAPTER 4620, CLEAN INDOOR AIR4620.3900Minn. R. 4620.3900PURPOSELast amended: 2012Year: 2026Length: 26 wordsOfficial source The purpose of parts 4620.3900 to 4620.4800 is to protect public health by ensuring acceptable air quality in the operation and maintenance of indoor ice arenas.PreviousMinn. R. 4620.3724NextMinn. R. 4620.3910