What barrier components are included in Level III preservation?

• A. Dehumidification only
• B. Flexible bag, drop shroud, and rigid shelter
• C. Drop shroud and rigid shelter
• D. Flexible bag only

Answer: (B)

Level III preservation relies on a layered barrier system to protect equipment from moisture, dust, and physical damage during long-term storage. The best protection includes a flexible bag that forms an initial sealed enclosure around the item, a drop shroud that covers access areas and helps maintain isolation, and a rigid shelter that provides a sturdy outer shell to guard against impacts and environmental ingress. Together these barriers establish a controlled micro-environment, reducing the chance of corrosion or degradation over time, which is why this combination is correct. Dehumidification alone or a single barrier like just a bag or just a shelter does not provide the same level of isolation needed for Level III preservation.