DIN EN IEC 62311 / VDE 0848-311

The DIN EN IEC 62311 standard regulates the assessment of electrical and electronic equipment with regard to human exposure to electromagnetic fields (0 Hz to 300 GHz). Here is a structured overview: Purpose: To ensure that devices comply with the limits for exposure to electromagnetic fields Area of application: Devices for which no product-specific standard exists (e.g. household appliances, industrial equipment, telecommunications equipment)

Tests:

• Measurement of electric (E-field), magnetic (H-field) fields and contact currents during normal operation

• Evaluation of intentional (e.g. transmitters) and unintentional emitters (e.g. switching power supplies)

• Comparison of the measured values with reference limits or basic restrictions3

• If the limit values are exceeded: detailed evidence (e.g. field distribution analyses)

Documentation:

Description of the methods, uncertainty analysis and declaration of conformity in the test report. Updates (2019): Differentiation between intentional/unintentional emitters, consideration of non-uniform fields.

Content, scope and tests:

Content of the standard:

DIN EN IEC 62311 specifies assessment methods and conformity criteria to evaluate the exposure of persons to electromagnetic fields. The standard includes:

• Fundamentals: definitions of basic restrictions (direct biophysical effects) and reference levels (derived limits).

• Assessment procedure: Simple test: Comparison of the measured field strengths/currents with reference values. Complex assessment: If limit values are exceeded, detailed analyses (e.g. numerical simulations) are carried out. Uncertainty assessment: A relative measurement uncertainty of 30 % is applied as standard.

• Special scenarios: Multi-frequency sources: Summation of exposure across all frequencies. Non-uniform fields: Evaluation of the local field distribution.

Scope of application:

The standard applies to:

• Devices without a product-specific standard: e.g. IoT devices, medical devices, industrial controls.

• Frequency spectrum: 0 Hz (direct current) to 300 GHz (5G millimeter waves).

• Target group: Manufacturers, test laboratories and regulatory authorities.

• Exceptions: Devices with their own standards (e.g. cell phones according to IEC 62209).

Tests to be performed:

Test conditions:

• Operating conditions: Tests under realistic worst-case scenarios (e.g. maximum transmission power).

• Environment: Controlled laboratory conditions or field measurements.

• Frequency range: Depending on the highest internal frequency of the device (e.g. at 1 GHz: evaluation up to 5 GHz).

Sample preparation:

• Typical samples: Devices in series configuration, possibly with accessories (e.g. antennas).

• Measurement distance: Determination based on the typical usage distance (e.g. 20 cm for wearables).

Evaluation:

• Comparison with limit values: Reference values: E-field (e.g. 61 V/m at 100 kHz) and H-field (e.g. 0.16 A/m at 10 MHz).

• Basic restrictions: Specific absorption rate (SAR) at high frequency.

• Summation rules: Addition of the contributions of several frequencies or sources.

Documentation:

• Test report: Contains measurement methods, uncertainty analysis, device configuration and interpretation of results.

• Declaration of conformity: Clear statement on compliance with the limit values.

Alternative standards:

1. IEC 62479: Simplified conformity assessment procedure for low power devices (10 MHz - 300 GHz).

2. IEC 62232: Assessment of exposure from radio base stations.

3. ICNIRP guidelines: Internationally recognized limits for EMF exposure.

4. EN 50663: Framework standard for the assessment of radio equipment.