An indirect system could be each automatic and manual, according to the variety of suppression getting used.
Condensed Aerosol Fire-Extinguishing Systems, NFPA 2010; these systems use a combination of great https://patch.com/north-carolina/raleigh/classifieds/gigs-services/467764/safeguarding-lives-and-property-all-american-fire-protections-quarter-century-of-excellence