Confined space ventilation by shipyard welders: observed use and effectiveness

Area of Science:

• Occupational Health
• Industrial Hygiene
• Environmental Engineering

Background:

• Shipbuilding welding occurs in confined spaces, posing significant inhalation risks.
• Ventilation is used, but its effectiveness in controlling welding fume exposure is poorly documented.
• Understanding factors influencing exposure is crucial for worker safety.

Purpose of the Study:

• To assess the use and effectiveness of ventilation during welding in confined spaces in shipyards.
• To identify key parameters influencing welder exposure to particulate matter.
• To inform training for effective ventilation strategies in hot work environments.

Main Methods:

• Observational study of 65 welding scenarios in two shipyards.
• Recorded ventilation parameters (type, placement, airflow) and task characteristics (welding type, welder position).
• Monitored welder exposure to particulate matter and analyzed associations with ventilation and task variables.

Main Results:

• Mechanical ventilation was present in two-thirds of scenarios, but welders worked in dead spaces 53% of the time.
• Welding method, welder's proximity to fume, and air mixing significantly impacted exposure.
• Respiratory protection use was high (77-100%), but ventilation effectiveness varied.

Conclusions:

• Current ventilation practices in confined space welding are often insufficient.
• Subjective parameters like welding proximity and air mixing are key for exposure reduction.
• Targeted training on effective ventilation use during hot work is recommended.