The allowable span for common slab conditions may be found in SDI’s FDDM (Floor deck Design Manual) and can be purchased on this website. The designer should consider that the allowable span typically includes the Dead Load weight of the deck and concrete along with Construction Live load of 20 lb/ft2 or a 150-pound point load.  Or a 50lb/ft2 un-poured load.  If the construction live load will exceed these values before the concrete can harden, the designer should consult the deck manufacturer for advisement.  The allowable spans may also be found on the Deck Manufacturer’s catalogs.  If the required span exceeds the allowable span, shoring might be allowable depending on the slab condition.