What type of respirator shall be used when spraying aircraft polyurethane paint systems?

• A. Full-face respirator
• B. Supplied-air respirator
• C. Full face, hood, type C, continuous flow
• D. Chemical cartridge respirator

Answer: (C)

When spraying polyurethane aircraft paints, the main hazard is inhalation of isocyanates and solvent vapors, which requires a continuous source of clean breathing air and full facial protection. The best choice is a full-face hood connected to a Type C supplied-air system with continuous flow. The hood provides complete face and neck protection, and the continuous-flow supplied air creates positive pressure inside the hood, washing away contaminated air and keeping vapors from seeping in. This combination safely protects the eyes, face, and respiratory system during spraying, even in areas with limited ventilation. A simple full-face respirator or a chemical cartridge respirator relies on filters that can saturate and may not supply enough clean air, and may not adequately protect against isocyanate aerosols or provide eye protection against splashes. A hood without a continuous-flow system wouldn’t guarantee a steady supply of clean air, increasing exposure risk.