Final answer:
The fire officer's role when using a purchase order to obtain a service is to identify the need, create a purchase order, and follow purchasing procedures.
Step-by-step explanation:
The fire officer's role when using a purchase order to obtain a service is to:
Identify the need for a particular service, such as equipment repair, training, or consulting.
Create a purchase order with the necessary details, including the service provider's information and the desired service.
Follow the established purchasing procedures to ensure compliance with regulations and budget constraints.
By using a purchase order, the fire officer can efficiently acquire the necessary services while maintaining accountability and transparency in the procurement process.