The dust particles present in air can be minimised by extraction ventilation .

Answer

### Step-by-Step Solution:

1. **Understanding the Statement**: The statement claims that dust particles in the air can be minimized using extraction ventilation. We need to evaluate whether this is true.

2. **Defining Extraction Ventilation**: Extraction ventilation is a method used to remove contaminated air from a space. It involves a system designed to capture and filter out pollutants, including dust particles, from the air.

3. **Components of Extraction Ventilation**:
- **Hood**: This is the part that captures the polluted air containing dust particles.
- **Duct**: The duct transports the captured air from the hood to the dust collector.
- **Dust Collector**: This component filters out the dust particles from the air, allowing clean air to pass through.
- **Exhaust Fan**: The exhaust fan helps in expelling the filtered air back into the environment, ensuring that the air released has a minimal concentration of dust.

4. **Process Description**:
- The polluted air, which contains dust particles, enters through the hood.
- The air is then directed through the duct to the dust collector.
- In the dust collector, dust particles are precipitated out of the air, effectively reducing the concentration of dust.
- The clean air, now filtered, is expelled by the exhaust fan.

5. **Conclusion**: Since extraction ventilation effectively captures and removes dust particles from the air, the statement is true. This method is an efficient way to minimize the level of dust particles in the air.