Final answer:
The three main areas of focus are the comprehensive cleaning of the air conditioning system, establishing a regular maintenance program, and reviewing cleaning practices at other facilities to ensure health and sanitation standards are maintained.
Step-by-step explanation:
The three main areas of focus when cleaning the back of the store, particularly in the context of preventing infections, would be the cleaning of the air conditioning system, the implementation of a regular maintenance program, and the review of cleaning practices at other facilities. The comprehensive cleaning of the air conditioning systems helps prevent the growth of harmful microorganisms that can affect both staff and customers' health. A regular maintenance program ensures that any potential issues are addressed promptly, thus avoiding the build-up of biofilms or other contaminants. Reviewing cleaning practices across all facilities ensures consistency in cleanliness standards and improves overall store hygiene.