Question 98Refrigeration & AC - QMED

The correct answer is D) phosgene gas. When chlorinated fluorocarbon refrigerants, such as those used in HVAC systems, are exposed to open flames or hot surfaces, they can decompose and form phosgene gas. Phosgene is an extremely toxic gas that was used as a chemical weapon in World War I. This reaction is a serious safety hazard that can occur if refrigerants are improperly handled near ignition sources. The other answer choices are incorrect. Water vapor, petroleum crystals, and carbon monoxide are not the primary decomposition products of chlorinated fluorocarbon refrigerants under these conditions.