What is the primary concern when stacking boxes of thermite welding kits?

When stacking boxes of thermite welding kits, the primary concern should be height restrictions. This is due to the unique nature of thermite, which involves highly exothermic reactions that can produce extreme heat. If boxes are stacked too high, it can lead to instability, making it easier for them to topple over. Such situations could potentially result in dangerous spills or accidents, especially considering that thermite is a reactive material. Maintaining an appropriate height ensures not only safety in terms of structural stability but also helps in managing the risk of potentially hazardous reactions.

While weight distribution is important to some extent, the primary focus tends to be more about preventing a stack from becoming too tall and unstable. Similarly, while fire hazards are always a consideration when dealing with any welding materials, the immediate concern during stacking is directly related to how high the boxes are placed. Humidity effects are also relevant in terms of storage conditions, but they are secondary compared to the primary concern of maintaining a safe and stable height when stacking the boxes.