Medical devices are intended for use directly or indirectly on humans and hence risk associated with a medical device must be assessed. The presence of a large number of medical devices with varying uses makes it difficult to assess the regulatory requirements of each device. For this reason, various regulatory bodies have assigned different classes to medical devices based on the use, design complexity and risk posed when they are used. This classification of devices based on risk enables regulatory bodies to define different regulatory requirements & hence different review routes for bringing medical devices to the market.

US FDA recognizes three classes – Class I, II & III for medical devices. This classification is based on the level of control necessary to assure safety & effectiveness. The classification procedures of US FDA are defined in 21 CFR 860.

The European Union recognizes four classes – Class I, IIa, IIb and III. Class I includes Class I sterile, Class I measuring and Class I reusable surgical instruments. The classification rules as per the EU regulations are outlined in Annex VIII of EU MDR and Article IX of MDD. These rules consider the duration of contact, invasiveness, and nature of contact among other factors for classification of devices.

Classification of devices under other regulations follow a pattern similar to US FDA and EU and maybe combination of these risk classifications.