FDA Accessory Proposal Shows How Device Classes I, II and III Work

The FDA has proposed placing seven types of medical device accessories into Class I, the lowest-risk device class, in a Federal Register notice published Aug. 17. The list includes the tube that connects blood pressure cuffs to a noninvasive blood pressure system, a sterile plug for urological catheters, a detachable suction sleeve for smoke-evacuating surgical pencils, and chargers for battery-powered surgical instruments.

Each of these accessories reached the market as part of a submission for another device, such as a 510(k), De Novo request or premarket approval application. FDA says that as a result an accessory "may be subject to more than general controls on account of the parent device," even when general controls alone would be enough for the accessory on its own. Comments are due Oct. 16, 2026, and the notice says it "does not represent FDA's final determination."

The proposal turns on the three-class system at the center of US device regulation.

Three classes, three levels of control

Section 513 of the Federal Food, Drug, and Cosmetic Act, as the notice puts it, "defines three classes of devices, which are class I (general controls), class II (special controls), and class III (premarket approval)." FDA's regulatory controls page says each device is assigned to a class "based on the level of control necessary to provide reasonable assurance of its safety and effectiveness," and that controls increase from Class I to Class III.

General controls apply to every device unless a regulation exempts it. The notice lists provisions on adulteration and misbranding, registration and listing, records and reports, and good manufacturing practices. Special controls are added for Class II devices, where FDA says general controls alone are insufficient and there is enough information to set further requirements. Class III covers devices that support or sustain human life, are of substantial importance in preventing impairment of health, or may present a potential unreasonable risk of illness or injury, where general and special controls are not enough. Those generally need premarket approval.

According to FDA's classification page, the agency has classifications for about 1,700 generic types of devices, grouped into 16 medical specialty panels. Classification depends on a device's intended use and indications for use, and on the risk it poses to the patient or user.

Why the class decides the route to market

The class largely determines what a company must file. FDA says that if a device is Class I or II "and if it is not exempt, a 510k will be required for marketing," while Class III devices require a premarket approval application, with an exception for certain devices on the market before 1976. Many low-risk devices need no premarket submission at all: FDA says about 572, or 74%, of Class I device types are exempt from premarket notification. Exempt devices still have to meet general controls, and exemptions carry limitations set out in the regulations.

That is what is at stake in the accessory proposal. If FDA finalizes it as proposed, each accessory would get its own classification regulation and would be "class I, exempt from the premarket notification procedures," according to the notice. A company making a replacement charger or catheter plug of those types would then not need a 510(k) for it, as long as the limitations on exemption do not apply.

Limits on what qualifies

The notice sets three conditions for an accessory to be classified separately into Class I: it is not life-supporting or life-sustaining or of substantial importance in preventing impairment of health, it does not present a potential unreasonable risk of illness or injury, and general controls alone are sufficient. FDA also says that "device-specific accessories," designed around the dimensions or geometry of one parent device, are not generally eligible, because design controls matter for making sure they fit the parent device.

The distinct classification process comes from the FDA Reauthorization Act of 2017, under which the agency periodically proposes accessories for Class I and seeks comment. This list followed a request for public input that FDA posted on Dec. 5, 2025.