In case of a fire, before the firemen use the water hoses, they shut off the main electrical supply for the area. Explain why they do this.

Explanation

### Step-by-Step Text Solution

1. **Understanding the Situation**: In the event of a fire, firemen need to use water hoses to extinguish the flames. However, before they do so, they take a crucial safety step.

2. **Shutting Off the Electrical Supply**: The firemen shut off the main electrical supply for the area where the fire is located. This is done to prevent any electrical hazards that could arise during firefighting efforts.

3. **Risk of Electrical Appliances**: Many buildings have electrical appliances that may still be connected to the power supply. If the electricity is still on, these appliances can pose a danger when water is applied.

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