Control of paint overspray in autobody repair shops

Area of Science:

• Occupational Health and Safety
• Industrial Hygiene
• Environmental Engineering

Background:

• Worker exposure to paint overspray in autobody shops poses significant health risks.
• Existing engineering controls for paint overspray require evaluation for effectiveness.

Purpose of the Study:

• To evaluate the effectiveness of commercially available controls for reducing worker exposure to paint overspray.
• To compare different types of spray-painting booths and spray guns.
• To assess respirator usage and fit in autobody repair shops.

Main Methods:

• Field evaluations in six autobody shops and a manufacturer's test facility.
• Measurement of particulate overspray concentrations in the worker's breathing zone.
• Visualization of airflow patterns and measurement of air volumes and velocities.
• Observation of respirator usage and quantitative fit testing.

Main Results:

• Downdraft spray booths showed lower particulate overspray concentrations than crossdraft and semidowndraft booths.
• Vehicle preparation stations demonstrated limited overspray control capabilities.
• High-volume low-pressure (HVLP) spray guns reduced particulate overspray by 50% but did not significantly impact solvent concentrations.
• Inappropriate respirator maintenance and fit were observed in most shops, indicating a lack of formal respirator programs.

Conclusions:

• Downdraft spray booths are superior for controlling particulate overspray in autobody painting.
• Improvements in spray gun technology can reduce particulate emissions.
• Effective worker protection requires not only engineering controls but also proper respirator programs, including maintenance and fit testing.