According to Painter A and Painter B, who is correct regarding the use of a charcoal cartridge respirator for spraying urethane paints?

In this scenario, Painter B is identified as correct regarding the use of a charcoal cartridge respirator for spraying urethane paints. This conclusion is based on the fact that charcoal cartridge respirators are not suitable for protecting against the specific hazards associated with certain chemical vapors, including those released by urethane paints.

Urethane paints often emit isocyanates, which can be harmful to respiratory health. A charcoal cartridge respirator may not adequately filter these types of harmful vapors, potentially allowing dangerous exposure. Instead, a more effective type of respiratory protection, such as a supplied-air respirator or a respirator with a specific filter designed for isocyanates, should be used to ensure safety when working with these materials.

Understanding the requirements for respiratory protection in environments where toxic chemicals are present is crucial for maintaining safety standards while working with hazardous substances. Thus, Painter B's assertion emphasizes the importance of using the correct respiratory equipment in accordance with safety guidelines established for chemical handling.