The best safety standard for LEDs at the moment is IEC 60825. However, when this is applied to certain areas it puts LEDs at a particular disadvantage.
IEC 60825 is a very useful standard and is used to classify products into risk groups. The risk group then determines what precautions need to be taken to keep the user safe while using the product. Lower risk devices (class 1 and class 2) have few controls and devices tend to be inherently safe for their application.
For higher risk groups (class 3R, 3B and 4) the controls are more stringent, which can put high-power LED devices at a disadvantage when compared to traditional products.
One example of this is in Non Destructive Testing. There are currently no safety controls for the light output of existing mercury vapor UV lamps (operating at 365 nm wavelength).
However the LED-based lamp that we have developed falls into class 3R of IEC 60825. This means that we have to put in controls, such as a LED radiation emission warning, which make our product less competitive.
This is despite the fact that the LED lamp is safer since the mercury vapor bulb produces UVB and UVC, which are subsequently filtered out. These filters are fragile and susceptible to damage which can let the harmful radiation through. The LED spectrum only containsUVA.
Also the mercury vapor lamps are twice as powerful, so if we were to try to compete on the basis of power we may need to produce a class 3B, or class 4 LED product! This would mean that we would have to incorporate controlled access to the lamp, implement a beam-stop device and recommend that the user appoint a laser safety officer to ensure procedures are established for the safe use of the product.
There is no doubt that the controls in 60825 are necessary to protect users. However, as LED products become more powerful and start to move up the risk groups these controls start to affect the competitiveness of LED products with traditional solutions which are less tightly controlled.
LEDs Magazine welcomes comments on any of our articles. Please contact the editor, Tim Whitaker.