Which hazmat storage practice is correct?

• A. Keep containers open to vent vapors
• B. Store next to ignition sources
• C. Segregate incompatible materials and use secondary containment
• D. Mix materials to reduce volume

Answer: (C)

The key idea here is that you store hazmat by keeping incompatible materials apart and providing a secondary containment system to catch any leaks or spills. Segregating materials by compatibility prevents dangerous chemical reactions, toxic vapor generation, or fires that could occur if reactive substances come into contact. Secondary containment—like spill pallets, trays, or dikes—captures leaks and limits the spread, making cleanup easier and reducing environmental and safety risks. This approach also supports regulatory and safety practices by having a defined space and means to handle spills.

Leaving containers open to vent vapors is unsafe because it releases hazardous vapors into the work area. Storing hazmat next to ignition sources raises the risk of fire or explosion. Mixing different materials to “reduce volume” can lead to unpredictable and violent reactions, creating far greater hazards.