South Carolina Nail Technician Practice Test

A friction blister is categorized as a bulla because it is characterized by a raised, fluid-filled lesion that is larger than a vesicle, typically measuring over 0.5 centimeters in diameter. Friction blisters develop due to friction or pressure on the skin, leading to the separation of skin layers and the accumulation of fluid in the space created.

In contrast, vesicles are smaller fluid-filled lesions, usually under 0.5 centimeters, while pustules contain pus and macules are flat discolorations on the skin without any elevation. Understanding the size and characteristics of these lesions helps in identifying and categorizing skin conditions accurately.