Standard positioning and version
IEC 62471-6:2022 "Photobiological safety of lamps and lamp systems - Part 6: Ultraviolet lamp products" is a specialized standard published by the
International Electrotechnical Commission (IEC), specifically designed for lamp products primarily emitting ultraviolet radiation, providing radiation
safety assessment, risk grouping, and safety requirements. This standard was officially released in October 2022, with the corresponding EU version
being EN IEC 62471-6:2023.
Scope of application determination
The standard is applicable to lamps and systems that primarily emit ultraviolet radiation (wavelength 180 nm to 400 nm). Typical products include
UV LED lamps, low and medium pressure mercury lamps, excimer lamps, deuterium lamps, etc. The judgment condition is that the ultraviolet band
(180 nm-400 nm) accounts for more than 50% of the total radiation power from 180 nm to 3000 nm. If the proportion of ultraviolet radiation is less
than 50%, the basic standard IEC 62471 should be used for evaluation.
The standard clearly covers ultraviolet medical diagnostic and cosmetic equipment, but does not include general lighting fixtures, infrared heating
lamps, fluorescent lamps for sunbathing (covered by IEC 60335-2-27 and IEC 61228), and ultraviolet therapeutic medical equipment (covered by
IEC 60601-2-57).
Risk grouping system
The standard divides ultraviolet lamp products into four risk levels based on the degree of light radiation hazard:
RG-0 (Exemption Group): No photobiohazard under normal use conditions
RG-1 (low-risk group): Safe under normal behavior, no special protective requirements
RG-2 (medium risk group): relies on natural avoidance reactions of humans (such as glare discomfort) to ensure safety
RG-3 (high-risk group): Even short-term exposure can pose hazards and requires strict engineering control
Time weighted average (TWA) exposure concept
Due to the photobiological effects of ultraviolet radiation being based on the total cumulative dose, the standard adopts the concept of "time
weighted average" exposure. The evaluation distance is determined based on the actual application scenario and expected exposure duration,
rather than a fixed distance. For example, the evaluation distance for household ultraviolet cleaning lamps is usually 0.5 meters, professional
ultraviolet air disinfection equipment can reach 1 meter, and upper room ultraviolet (GUV) lamps may be 2-3 meters. This is significantly different
from the more general evaluation method in the basic standard IEC 62471.
Core testing content
The test needs to be conducted in the maximum output power mode of the lamp, using a spectral radiometer and radiometer to measure the
radiation intensity in the 180nm – 400nm band, with a focus on evaluating the UV-B and UV-C bands. The test needs to simulate the worst-case
exposure level, compare the measured effective irradiance with the risk grouping limit specified in the standard, and determine the corresponding
risk level. For the 180nm-200 nm wavelength range, due to strong oxygen absorption, testing is only conducted under specific conditions.
Engineering control requirements
For RG-2 and RG-3 grade ultraviolet lamp products, the standard proposes mandatory engineering safety measures, including:
Protective casing or shielding device
Human proximity sensor
UV beam direction control
Alignment requirements for ultraviolet lamps in the upper room
Delay start timer
Exposure time control or automatic shutdown function
Interlocking protection device for detachable baffle
Label and User Information Requirements
Manufacturers must provide complete safety information in product labels and user manuals, including:
Risk level identification (RG-0 to RG-3)
Warning symbols and language for ultraviolet radiation
Safe use distance and maximum allowable exposure time
Explanation of Risk Reduction Measures
Limited usage conditions
Maintenance and service information
Applicable scenario description
Overview of Certification Process
The complete IEC 62471-6 certification usually includes the following steps: submitting product technical information (specifications, circuit diagrams,
instructions for use, etc.) → preparing representative samples (2-3 finished lamps) → conducting spectral scanning and irradiance measurement in the
laboratory → calculating hazard values according to weighting functions and comparing them with limit values → determining risk levels → issuing test
reports and compliance certificates. The testing cycle for UV products is usually 10-15 working days.
Relationship with other standards
IEC 62471-6 is the sixth part of the IEC 62471 series of standards, used in parallel with the basic standard IEC 62471:2006. If the product involves
electrical safety, EMC and other requirements, comprehensive certification must be conducted in conjunction with relevant standards such as
IEC 60335 and IEC 60601. In the EU market, this standard is usually used as the technical basis for photobiological safety assessment in CE certification.
