Which hazard may cause a service engineer to cough or experience irritation in the eyes and throat?

Thermal decomposition is the correct answer because it refers to the breakdown of refrigerants into harmful by-products when they are exposed to high temperatures. This process can release toxic gases that may irritate the eyes and throat, leading to coughing or respiratory discomfort. These by-products can also be hazardous if inhaled, making it crucial for service engineers to be aware of thermal decomposition risks when handling refrigerants.

Understanding how refrigerants can decompose at elevated temperatures helps engineers recognize the importance of maintaining proper equipment conditions and safe handling practices to minimize exposure to harmful fumes. Safe working practices, such as wearing appropriate personal protective equipment and ensuring good ventilation when dealing with potentially decomposing gases, are essential for reducing health risks in the workplace.