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Microbial biofilms representing both Gram-positive and Gram-negative bacteria were artificially coated onto aluminum metal surfaces that are commonly used in building spacecraft. Changes in bacterial numbers were monitored over time on metal test sections by conventional spread plate technique and polymerase chain reaction (PCR). Conventional standard plating technique did not recover desiccated bacterial biomass from either glass or aluminum metal surfaces even with a density of 106 cells per coupon. However, whole-cell PCR (without extracting DNA) showed a positive signal for a density of 105 dehydrated microbial cells. Electron and epifluorescent microscopic examinations revealed that bacteria entered a non-cultivable state once the water activity was reduced to minimum. However, a simple DNA extraction protocol combined with PCR amplification of a specific 16S rDNA fragment improved the recovery of non-viable desiccated microbial biofilm from the metal test sections.