It shall be the duty of every school board and the governing body of nonpublic schools to provide for the health conditions of the school by furnishing each school with sanitary facilities and a supply of water suitable for drinking, and to maintain sanitary conditions, and to install electrical service and adequate lighting facilities and a telephone when such services are available to the school, except that for a temporary school to be operated for less than one school term, the school board shall have discretionary authority to determine whether or not to install electric and telephone services.