Describe the risk classification system for medical devices according to the FDA.

The FDA, or Food and Drug Administration, classifies medical devices into three classes – Class I, Class II, and Class III – based on the level of risk they pose to patients and users. This classification determines the regulatory controls required for each type of device. Class I devices are considered low-risk and are subject to the least regulatory control. These devices typically pose minimal potential for harm if they malfunction or are used improperly. Examples of Class I devices include bandages, examination gloves, and manual stethoscopes. Most Class I devices are exempt from premarket notification (510(k)) requirements, meaning that manufacturers do not need to submit a premarket notification to the FDA before marketing the device. Class II devices are considered moderate-risk and are subject to more regulatory controls than Class I devices. These devices pose a greater potential for harm than Class I devices, but the risks can be mitigated through special controls. Examples of Class II devices include powered wheelchairs, infusion pumps, and surgical drapes. Most Class II devices require premarket notification (510(k)), which demonstrates that the device is substantially equivalent to a legally marketed predicate device. Special controls for Class II devices may include performance standards, labeling requirements, and postmarket surveillance. Class III devices are considered high-risk and are subject to the most stringent regulatory controls. These devices typically support or sustain human life, are of substantial importance in preventing impairment of human health, or present a potential unreasonable risk of illness or injury. Examples of Class III devices include implantable pacemakers, heart valves, and high-frequency ventilators. Class III devices typically require premarket approval (PMA), which involves a thorough review of the device's safety and effectiveness by the FDA. The PMA process is more complex and time-consuming than the 510(k) process. The FDA's risk classification system ensures that medical devices are subject to the appropriate level of regulatory control based on their potential risks.