LED Lighting fixtures: type of protection “op is”
LED technology improves year after year with even more high-power output and the risks for hazardous areas continue to grow. There are high-powered LED lighting fixtures that can ignite air-borne particles.
This risk is called optical radiation and it is highly present in hazardous areas where dust and dirt are the result of the normal activities: when a high-powered LED luminaire gets dirty, the dirt absorbs optical radiation energy, causing temperatures to rise and potentially creating an ignition source which may cause an explosion.
As a reliable supplier of LED lighting fixtures, FEAM is committed to any issue related to the safety of people and plants and for this reason, after investigating the problem of optical radiation, the Company has identified those lamps which are most subject to this problem and has certified them with the “Op is” mark.
The marking “op is” defines that the equipment is inherently safe (“is”) against the optical radiations, this means that the product cannot create an ignition source. With modern LEDs the highest risk is close to the source. The risk gets weaker as it travels away from the source.
There are four key factors that determine if otherwise harmless light can become an ignition source:
* the energy output of the light source,
* the focal point of the light waves,
* the distance from the light source and
* the presence of an energy-absorbing material (an absorber like a mix of oil, dirt and grease).
The EN/IEC 60079 -28 standard defines which tests must be performed on dirty products in case of optical radiation. This standard has a great importance as it is the only one which takes into consideration the variable “dirty equipment”. The most common standards define the tests only for products which are new and fresh of the manufacturing line in their cleanest state.