I. QCVN 134:2024/BTTTT — Vietnam's National Technical Regulation on SAR

QCVN 134:2024/BTTTT directly references the international standard IEC/IEEE 62209-1528:2020 as the technical basis for all SAR measurement methods. This means that all requirements regarding test equipment, measurement environment, test procedures, and measurement uncertainty set out in IEC/IEEE 62209-1528:2020 become mandatory requirements when conducting SAR testing under QCVN 134:2024/BTTTT in Vietnam.

II. Stringent Technical Requirements for the SAR Testing Environment

Since QCVN 134:2024/BTTTT references IEC/IEEE 62209-1528:2020, the testing environment requirements set out in this international standard become mandatory compliance obligations in Vietnam.

The two most critical requirement groups are:

2.1 Temperature Control Requirements

•       The ambient temperature of the measurement room and the temperature of the tissue-equivalent liquid must be maintained within the range of 18°C to 25°C.

•       The temperature of the tissue-equivalent medium during SAR measurements must remain within ±2°C of the temperature at which the dielectric properties were measured. If the temperature deviation exceeds this limit, the dielectric properties must be re-measured.

•       Dielectric properties must be measured within 24 hours prior to conducting SAR measurements and must be re-measured after every 48 hours of continuous use.

2.2 Ambient Electromagnetic Interference Control Requirements

•       The SAR error caused by ambient electromagnetic interference from the surrounding environment must be ≤ 0.012 W/kg (equivalent to 3% of the reference level of 0.4 W/kg).

•       If this threshold is exceeded, the test laboratory must either apply mitigation measures or demonstrate that the interference contribution is less than 10% of the actual SAR value of the device under test, and account for it in the measurement uncertainty budget.

•       The device under test must not be connected to any live wireless network during the measurement.

III. Dt&C Vina — Achieving the Highest Level of Compliance with QCVN 134:2024/BTTTT

Dt&C Vina has proactively chosen the highest level of environmental control — placing each SAR measurement system inside a dedicated, independent shielded chamber (shield room).

3.1 Independent Shielded Chamber System

With dedicated independent shielded chambers (shield rooms) for each SAR measurement system, Dt&C Vina ensures:

•       Ambient electromagnetic interference levels are maintained at near-zero — significantly below the 0.012 W/kg threshold required by the standard, completely eliminating measurement errors caused by environmental interference.

•       Each chamber operates fully independently — with no cross-interference, enabling simultaneous testing across multiple projects.

3.2 Dedicated Precision Climate Control Systems — Maintaining Stable Temperature 24/7 Across All SAR Testing Rooms.

The temperature control system in each shielded chamber is independently configured and managed, maintaining stable conditions within the 18°C–25°C range as required by QCVN 134:2024/BTTTT and the referenced standard IEC/IEEE 62209-1528:2020.

Dt&C Vina has installed a dedicated air conditioning system for the SAR test chambers

IV. Practical Benefits for Customers

•       Parallel Testing Across Multiple Projects: Independent shielded chambers allow simultaneous testing of multiple product projects at the same time.

•       Accurate and Reproducible Results: A fully stable and controlled measurement environment eliminates random errors caused by environmental interference. Dt&C Vina's measurement results offer high reproducibility, suitable for both repeat testing and longitudinal result comparison.

•       Reliable Turnaround Commitments: With no dependency on external wireless conditions, Dt&C Vina faces no risk of measurement delays caused by unexpected interference. Customers receive firm testing schedules and guaranteed result delivery timelines.

•       Multi-Market Report Validity: Test reports issued by Dt&C Vina fully satisfy the requirements of QCVN 134:2024/BTTTT for the Vietnamese market, while also serving as a strong reference for SAR-regulated export markets including FCC (USA), CE (EU), MIC (Japan), and ISED (Canada).

•       Product Information Confidentiality: Each project is conducted within a completely physically isolated chamber, ensuring that project information and test samples remain strictly confidential, in full compliance with non-disclosure agreements signed with customers.

V. Conclusion

QCVN 134:2024/BTTTT marks a pivotal milestone in the quality management of wireless devices in Vietnam. Dt&C Vina is committed to continuously investing in world-class infrastructure and equipment, and to rigorously adhering to testing procedures — ensuring customers receive the highest quality SAR testing services: accurate, reliable, and ready to meet the demands of both domestic and international markets.