In case of an emergency, as defined under Section 1102, the board, upon adopting a resolution passed by a four-fifths vote of all its members, declaring and determining that public interest and necessity demand the immediate expenditure of public money to safeguard life, health, or property, may expend, or enter into a contract involving the expenditure of, any sum needed in the emergency without observing the provisions requiring contracts, bids, or notice. If notice for bids to let contracts will not be given, the board shall comply with Chapter 2.5 (commencing with Section 22050).