The sensitivity of 30 strains of bacteria, isolated from damaged oil-paper manuscripts and leather goods, to gamma-rays (₆₀Co). The LD₁₀ values for vegetative cells and spores from manuscripts were 560-1150 Gy and more than 1500 Gy. Most spores had LD₁₀ values of 2220-2500 Gy. Bacterial strains isolated from leather were more resistant to gamma-irradiation with an LD₁₀ value of around 3330 Gy. No geographical differences were observed in the radiosensitivities of bacteria regardless of the source, whether from museums, libraries, or archives in the USSR. -- AATA