Classification Overview
Thai FDA · ASEAN AMDD · MoPH Notification B.E. 2562
Four-Class Risk System
Thailand's classification follows the ASEAN Medical Device Directive (AMDD) four-class risk framework:
| Class | Risk Level | Approval Pathway | Examples |
|---|---|---|---|
| 1 | Low | Listing (Positive List only) | Non-sterile bandages, examination mirrors, spatulas, some non-invasive accessories |
| 2 | Low-moderate | Notification | Blood pressure cuffs, ultrasound equipment, non-implantable orthopaedic supports |
| 3 | Moderate-high | Notification | Lung ventilators, infusion pumps, bone screws (non-absorbable) |
| 4 | High | License | Heart valves, pacemakers, coronary stents, implantable defibrillators, active implants |
Classification Rules
Classification is based on the MoPH Notification on Risk Classification under the Medical Device Act B.E. 2562. Rules apply:
1. Invasiveness
| Type | Description |
|---|---|
| Non-invasive | Does not penetrate body — generally Class 1 or 2 |
| Invasive into orifice | Enters natural body openings |
| Surgically invasive | Penetrates body through surgical incision |
| Implantable | Intended to remain in the body after procedure — Class 3 or 4 |
2. Duration of Contact
| Duration | Definition |
|---|---|
| Transient | Less than 60 minutes |
| Short-term | 60 minutes to 30 days |
| Long-term | More than 30 days |
3. Active vs Non-Active
Active devices (requiring an electrical, heat, light, or other energy source) are generally classified higher than non-active devices with equivalent invasiveness and duration.
4. Anatomical Location
Devices in contact with the central nervous system, cardiovascular system, or in direct blood stream contact carry higher classification.
5. Intended Purpose
The intended purpose stated by the manufacturer is the starting point. Where multiple uses apply, the riskiest use determines the class.
Tie-Breaking Rule
If multiple rules apply to a single device, the highest class applies.
Positive List for Class 1 — TH-Unique
Class 1 devices may only use the Listing pathway if they appear on the Thai FDA's Positive List of eligible Class 1 devices. Not all Class 1 devices are on the Positive List — devices not listed must use the Notification pathway even if their risk class is 1.
Implication: Check the current Positive List before assuming a Class 1 device can use the Listing pathway. The Positive List is updated periodically — download the current version from the Thai FDA/MDCD website.
IVD Classification
IVD devices use ASEAN AMDD IVD classification rules within the same Class 1–4 system:
| IVD Class | Typical Examples |
|---|---|
| 1 | General lab instruments, sample collection containers, culture media |
| 2 | Blood glucose meters, pregnancy tests, urine test strips |
| 3 | HIV confirmatory tests, hepatitis B/C tests, tumour markers |
| 4 | Blood donor screening: HIV, HCV, West Nile virus, syphilis |
IVD classification considers: user expertise (professional vs lay), individual patient risk from incorrect results, public health significance.