I. Applications and Optical Radiation Risks of Ophthalmic Instruments
Ophthalmic instruments are specialised medical devices used for diagnosis, treatment, and surgery in ophthalmology. They include slit‑lamp microscopes, ophthalmoscopes, refractometers, perimeters, optical coherence tomography (OCT) devices, laser therapy systems, and femtosecond lasers. These devices deliver light into the human eye for examination, measurement, imaging, or therapeutic purposes.
However, optical radiation, while enabling clinical value, also carries potential safety risks. The light emitted by ophthalmic instruments may contain visible, ultraviolet, and infrared wavelengths. Studies indicate that under unfavourable conditions, devices such as surgical microscopes may cause thermal damage to the patient’s retina. Photochemical risks are equally significant, particularly from short‑wavelength blue light components. When the pupil is dilated during examination, the amount of light entering the eye increases, raising the risk of retinal injury. In addition, ultraviolet radiation can cause keratitis or lens opacification, while infrared radiation, due to its strong penetrative power, may produce thermal effects that damage fundus tissues. Therefore, a rigorous optical radiation safety assessment for ophthalmic instruments is essential.
II. Overview of ISO 15004‑2 Testing Standard
ISO 15004‑2, entitled “Ophthalmic instruments — Fundamental requirements and test methods — Part 2: Light hazard protection”, is the core international standard for evaluating the optical radiation safety of ophthalmic instruments. It applies to all ophthalmic devices that direct optical radiation into the eye, including emerging equipment used for diagnosis, illumination, measurement, imaging, or alignment.
This standard classifies ophthalmic instruments into two groups:
Group 1 instruments: No potential light hazard exists; their radiation levels remain below the exposure limits under all conditions of use.
Group 2 instruments: Potential light hazards exist; their radiation levels may exceed the limits, requiring clear labelling and defined conditions for safe use.
The 2024 updated version introduced technical revisions in terms of definitions, exposure limit tables, and provisions for long‑term repeated exposure, making the standard clearer and more aligned with the latest research findings.
III. ISO 15004‑2 Optical Radiation Safety Testing Process
A typical test procedure in accordance with ISO 15004‑2 includes the following steps:
Instrument warm‑up and environmental preparation – Place the instrument under standard environmental conditions and allow sufficient warm‑up to ensure compliance with test specifications.
Spectral measurement and classification – Measure the spectral radiation emitted by the device and determine whether it belongs to Group 1 or Group 2 according to the standard.
Measurement of key parameters – Using calibrated optical radiometers, spectroradiometers, and other specialised equipment, measure key parameters such as corneal irradiance, lens irradiance, and retinal irradiance.
Exposure limit evaluation – For Group 1 instruments, verify that all radiation levels comply with the exposure limits. For Group 2 instruments, determine the time (t_max) or number of pulses (n_max) required to reach the recommended maximum exposure, and assess the cumulative risk of long‑term repeated use.
Data recording and reporting – Document all test data completely and compile a test report that meets the standard requirements for product registration, certification, or quality compliance.
IV. Testing Timeline and Costs
Testing timeline: The optical radiation safety test per ISO 15004‑2 typically takes 5 to 10 working days, depending on product complexity, the number of test items, and laboratory scheduling. For devices with a simple structure and a well‑defined spectral range, the timeline is shorter; for complex systems involving multiple light sources, pulsed modes, or long‑term exposure assessment, additional time is required.
Testing costs: Fees vary based on product type, testing difficulty, and the specific items required. The main cost drivers include: instrument classification (Group 1 vs. Group 2, with Group 2 requiring deeper evaluation), the number of test items (e.g., whether long‑term repeated exposure risk must be assessed), and whether additional support for medical device registration testing is needed.
V. Why Choose Shenzhen Zhongwei Testing
Shenzhen Zhongwei Inspection (CTNT) is a professional testing and certification body specialising in optical products and energy efficiency. With over ten years of experience in optoelectronic product testing and certification, we have served more than 10,000 clients and earned wide market recognition. We operate a state‑of‑the‑art optical laboratory and laser laboratory, with extensive practical experience in light hazard testing for ophthalmic instruments. We provide professional optical radiation safety and photobiological safety testing services for both laser and incoherent light products. Our fast turnaround times, professional reliability, and deep expertise have earned us high praise from customers in the optoelectronics industry.
