Multiple-component integral-structure dual-test sterility indicator, method of assembling physical components, selected spores, and chemical constituents in solution, within the indicator and arranged to enable dual-evaluations of bacterial-lethality of a dry-goods load, resulting from exposure to a selected saturated-steam sterilizing cycle. The chemical constituents are formulated to chemically produce reaction-product, which is quantitatively responsive to the combined effect of cycle steam temperature and time of exposure at that temperature, for providing a promptly-available spectroscopic evaluation of bacterial-lethality. Absorption of narrow-band selected visible-light wavelength by reaction-product, if any, of chemical-constituent solution, is used to quantitatively measure that combined-effect exposure. Subsequent to such prompt-response evaluation of bacterial-lethality, a biological evaluation of bacterial-lethality, utilizing the confined contents of the same test indicator, free of risk of ambient contamination of any such contents, by evaluating pH change, if any, due to live spore-growth, or the absence thereof, following a predetermined spore incubation period, utilizing the exposed liquid constituent-solution for such spore-culturing evaluation.