Which environmental condition affects the longevity of sterile items the most?

Extremes in humidity significantly affect the longevity of sterile items because high humidity can promote the growth of microorganisms and degrade packaging materials, leading to compromised sterility. When items are stored in environments with high moisture levels, there is an increased risk that the sterile barriers may become ineffective. This can result in moisture entering packaging, which can create an environment conducive to contamination. Conversely, extremely low humidity can also be problematic, as it may cause desiccation or drying out of certain materials, potentially compromising their effectiveness or integrity.

In contrast, normal room temperature, stable air pressure, and consistent light exposure typically have less of a direct impact on the sterility of items compared to the effects of humidity. Normal room temperature is generally considered safe for the storage of sterile items as long as it falls within a specific range, and stable air pressure is essential for maintaining a controlled environment but does not directly affect sterility itself. Consistent light exposure likewise has a minor role, and while some materials can degrade under excessive light, proper storage typically minimizes such risks. Therefore, humidity stands out as the most critical environmental factor for maintaining the integrity and longevity of sterile items.