Risk-Based Classification System for Non-In Vitro Diagnostic Medical Devices – Health Canada Guidance

Purpose and Legal Basis

This guidance document explains Health Canada’s risk-based classification system for non-in vitro diagnostic (non-IVD) medical devices under the Medical Devices Regulations. The system assigns devices to one of four classes (I, II, III, IV) based on the level of risk they present to patients and users. Higher classes require more rigorous premarket review and evidence of safety and effectiveness. The classification rules are set out in Schedule 1 of the Medical Devices Regulations. Guidance Document – Guidance for the Risk-based Classification System for Non-In Vitro Diagnostic (IVD) Medical Devices - Canada.ca

Key Classification Principles

Classification is determined by:

• Intended use – The purpose for which the device is marketed.
• Degree of invasiveness – Whether the device penetrates the body or contacts mucous membranes.
• Duration of contact – Transient (<60 min), short-term (≤30 days), or long-term (>30 days).
• Potential consequences of device failure – Risk of injury, illness, or death.

Devices are classified at the highest applicable level when multiple rules apply.

Classification Rules Summary

Rule 1 – Invasive Devices

• Devices that penetrate the body or contact mucous membranes.
• Class I: Non-invasive or minimally invasive (e.g., surgical instruments).
• Class II: Short-term invasive (e.g., catheters).
• Class III: Long-term invasive or surgically implanted (e.g., joint replacements).
• Class IV: Devices that administer or remove medicinal substances to/from the central nervous system or circulatory system.

Rule 2 – Non-Invasive Devices

• Devices that do not penetrate the body.
• Class I: General non-invasive (e.g., bandages, examination gloves).
• Class II: Devices that channel or store blood/fluids for transfusion or infusion.
• Class III: Devices that modify biological or chemical composition of blood/fluids.
• Class IV: Devices that administer or remove substances to/from the central nervous system or circulatory system.

Rule 3 – Active Devices

• Devices that rely on an energy source other than the human body.
• Class I: Low-risk active (e.g., simple pumps).
• Class II: Moderate-risk active (e.g., diagnostic ultrasound).
• Class III: High-risk active (e.g., ventilators).
• Class IV: Life-sustaining or life-supporting active devices (e.g., pacemakers).

Rule 4 – Special Rules

• Certain devices have fixed classifications regardless of other rules:
  • Class III: Devices intended to administer or remove drugs via the central nervous system or circulatory system.
  • Class IV: Devices that control, monitor, or affect vital physiological processes where failure could cause serious injury or death.

Practical Application

• Manufacturers must apply the rules sequentially and select the highest applicable class.
• Combination devices are classified based on the principal intended action.
• Software that drives or influences a device takes the classification of the hardware.

Implications for Premarket Requirements

• Class I: No licence required; establishment licence for importers/distributors.
• Class II: Licence required with quality system and safety/effectiveness evidence.
• Class III: Licence with detailed clinical evidence and quality system.
• Class IV: Licence with comprehensive clinical evidence, quality system, and highest scrutiny.

This risk-based system ensures regulatory effort is proportionate to device risk, protecting public health while facilitating innovation. Full classification rules, examples, decision trees, and application guidance are provided in the official Health Canada document. Guidance Document – Guidance for the Risk-based Classification System for Non-In Vitro Diagnostic (IVD) Medical Devices - Canada.ca