Are containers over 30 gallons allowed to be stacked in a storage room?

• A. Yes, they may be stacked
• B. They must not be stacked
• C. They may be stacked if on pallets
• D. They must be labeled

Answer: (B)

The main idea is safety and stability when storing large-volume liquids. Containers over 30 gallons are heavy, and stacking them creates a tall, unstable stack that can topple, crack, or leak. A spill or rupture in a storage room can quickly spread, create slippery floors, expose personnel to hazards, and hinder access or emergency response. To minimize these risks, large containers are kept in a single layer so each container is easily reachable, inspectable, and less prone to shifting or breaking under the weight of containers above. They can be placed on pallets to aid handling, but you should not stack more than one container high. Also ensure proper ventilation, separation from heat sources, and labeling as part of safe storage practices.