What must be present when storing flammable liquids on construction sites?

When storing flammable liquids on construction sites, it is crucial that they are kept away from ignition sources. Flammable liquids are volatile and can easily ignite if exposed to heat, sparks, or any other source of ignition. This precaution is essential to prevent fires and explosions, which pose significant risks to the safety of workers and the integrity of the construction site.

By ensuring that flammable liquids are stored at a safe distance from potential ignition sources, such as electrical equipment, open flames, or hot surfaces, you significantly reduce the likelihood of accidents. This safety measure is part of standard practices in hazardous material management and is required to maintain a safe working environment.

Other options, while they may have relevance in specific contexts, do not address the immediate risk of fire as directly as ensuring proper distancing from ignition sources. For example, labeling and visibility are important for safety awareness, but they do not inherently mitigate the risk of ignition. Storing liquids indoors might be suitable for security and temperature control, but it doesn't guarantee safety from ignition.