Clinical Engineering Bank

The regulatory authorities recognize different classes of medical devices based on their design complexity, their use characteristics, and their potential for harm if misused. Each country or region defines these categories in different ways. The authorities also recognize that some devices are provided in combination with drugs, and regulation of these combination products takes this factor into consideration.

Postmarket surveillance is the systematic

• Collection,
• Analysis,
• Interpretation, and
• Dissemination

FDA classifies medical devices based on the risks associated with the device. Devices are classified into one of three categories—Class I, Class II, and Class III.

Class I devices are deemed to be low risk and are therefore subject to the least regulatory controls. For example, dental floss is classified as Class I device.

Class II devices are higher risk devices than Class I and require greater regulatory controls to provide reasonable assurance of the device’s safety and effectiveness. For example, condoms are classified as Class II devices. 

Class III devices are generally the highest risk devices and are therefore subject to the highest level of regulatory control. Class III devices must typically be approved by FDA before they are marketed. For example, replacement heart valves are classified as Class III devices. 

The Medical Devices Bureau of Health Canada recognizes four classes of medical devices based on the level of control necessary to assure the safety and effectiveness of the device. Canadian classes of medical devices:

• Class I devices present the lowest potential risk and do not require a license, generally corresponds to Class I (ECD)

• Class II devices require the manufacturer’s declaration of device safety and effectiveness, generally corresponds to Class IIa (ECD), and

• Class III and Class IV present a greater potential risk and are subject to in-depth scrutiny, generally corresponds to Class IIb (ECD),

Examples include surgical instruments (Class I), contact lenses and ultrasound scanners (Class II), orthopedic implants and hemodialysis machines (Class III), and cardiac pacemakers (Class IV).

The classification of medical devices in the European Union is outlined in Annex IX of the Council Directive 93/42/EEC. There are basically four classes, ranging from low risk to high risk.

• Class I (including Is & Im)
• Class IIa
• Class IIb
• Class III

The classification of medical devices in Australia is outlined in section 41BD of the Therapeutic Goods Act 1989 and Regulation 3.2 of the Therapeutic Goods Regulations 2002, under control of the Therapeutic Goods Administration. Similarly to the EU classification, they rank in several categories, by order of increasing risk and associated required level of control.