All non-fully automatic oil burning installations must be operated under the direct supervision of a person holding what?

In the context of non-fully automatic oil burning installations, it is mandatory for these systems to be operated under the direct supervision of a person holding a Certificate of Fitness (COF) issued by the fire commissioner. This certification ensures that the operator has been trained and has adequate knowledge of fire safety regulations, the operation of the equipment, and emergency response procedures.

The requirement for direct supervision aims to mitigate the risks associated with oil burning operations, ensuring that a qualified individual is present to handle any potential malfunctions or hazardous situations that may arise during operation. This level of oversight is crucial for maintaining safety standards and compliance with local fire codes.

While other options involve regulations and requirements relevant to different contexts, none provide the specific authority and expertise that the COF represents in the operation of oil burning installations. The COF specifically designates individuals who have passed the necessary examinations and training pertinent to these operations, making it the correct answer in this scenario.