First consideration for chemical storage shall be based on its:

• A. Frequency of usage
• B. Compatibility with other chemicals
• C. Size of the container
• D. Alphabetical order

Answer: (B)

The first consideration in chemical storage is compatibility with other chemicals. Storing substances that react violently or produce toxic gases or heat when they contact each other can create serious hazards, so compatibility dictates how and where each chemical can be stored. This means grouping chemicals by their reactivity and hazard class and segregating those that can incompatibly interact—for example, keeping oxidizers away from fuels or organics, acids away from bases, and water-reactive materials away from moisture. Always check the safety data sheet for specific incompatibilities and use proper containment, labeling, and separation. Other factors like how often a chemical is used or the size of its container matter for logistics, but they do not override the need to prevent dangerous chemical interactions.