If a bag is accidentally ripped, the fertilizer should be confined to the immediate area and promptly recovered. That means having a solid floor and, for liquid fertilizers, a curb. The secondary containment space should be large enough to hold 125 percent of the contents of the largest container, plus the displaced volume of any other storage tanks in the area. Ideally, your fertilizer storage area should be separated from other uses. If the building must also serve as a machine shed or as housing for livestock, you may find it difficult to meet all the requirements for safe storage.
Stored fertilizers can pose a danger to firefighters and to the environment.
Reducing the fire risk in the storage area may be the first step, but other things can be done. You can reduce the damages by anticipating such emergencies. If a fire should occur, consider where the water will go and where it might collect. In making the storage area secure, also make it accessible, thus allowing you to get fertilizers out in a hurry. If fertilizer containers are damaged, the stored nutrients may be carried away by water and spread over a large area.