Final answer:
Masks of different sizes are essential in a medical setting to ensure proper fit and effective infection control during deliveries, providing safety for healthcare workers and patients.
Step-by-step explanation:
Masks of different sizes do need to be available at every delivery. This is crucial in a medical setting because the efficacy of a mask in preventing the spread of infection is greatly affected by its fit. Having a variety of sizes ensures that each healthcare provider, patient, and any other participant in the delivery room can select a mask that fits them correctly. Proper fit enhances the protective barrier against pathogens and provides safety for both the healthcare workers and the patients.