Which of the following is NOT a fire explosion precautionary measure that should be taken in storage places for hazardous materials?

Using electric fans in storage places for hazardous materials may not be a recommended precautionary measure, as they can potentially create sparks or static electricity, which could ignite flammable vapors or dust present in the area. In contrast, maintaining proper ventilation is essential as it helps prevent the accumulation of hazardous fumes and ensures that any airborne contaminants are diluted. Regularly checking for leaks is another critical safety measure, as it helps identify and mitigate hazards before they can lead to dangerous situations. Storing materials in approved containers is vital for maintaining safety standards and preventing spillage or unintended reactions between incompatible substances. Considering these factors, the use of electric fans in this context does not align with best practices for fire and explosion prevention among hazardous materials.