4.7.3 - Manual Application

Other than creating potentially explosive atmosphere, gas and powders produced by the spraying process could harm the operator health.

In the paragraph 4.7.3, the standard gives the directions regarding the manual application of the spray and it is reported:

“Contact with and inhalation of hazardous material sprayed shall be reduced by forced ventilation as far as possible. The airflow direction shall keep hazardous material (paint, solvents, coating powder) away from the breathing zone of the operator. This shall be achieved by the spray booth design and may be supported by e.g.

• Means to rotate workpieces;
• Optimizing of airlow direction to the work situation”
  

The standard also requires a minimum airflow for a correct breathing zone of the operator.

The requested airflow

• For spray booths for liquid coating material is calculated by

• For spray booths for powder coating material is calculated by

 

     Where:

• “v” is the average airflow velocity [m/s]
•  “Q_min” is the minimum fresh air volume flow required [m³/h]
• “w” is the width
• “l” is the lenght
• “A” is the area of the measurement plane