UV grade

May 10, 2022

UV grade

There are many mechanisms placed outdoors that are in direct contact with the elements over long periods of time.

One of these effects to which they are exposed repeatedly is solar radiation, which can adversely affect plastic mechanisms.

Nevertheless, it is not just solar radiation that affects them; there is also a wide range of electromagnetic waves that can cause some kind of change in the material the mechanism is made from: X-rays, gamma rays, long radio waves, etc.…

Therefore, it is of the utmost importance to conduct a study in order to pinpoint the direct effects of radiation, heat or humidity on the colour and other properties of these mechanisms; given that plastic is a material which, depending on the wave it is exposed to, may overheat and lose its qualities.

Hence, there is a need for ongoing testing to shed light on the evolution of the mechanisms exposed to these external, environmental and climatic factors.

Tests are carried out in accordance with the guidelines set forth by certain standards, such as ISO 4892, which specifies the different methods to be carried out for radiation simulation in laboratories.

Most of the tests carried out on these mechanisms make use of Accelerated Ageing Test Chambers with the aim of reproducing the ageing time and damage that the product could withstand. In this way, we can keep track of the evolution of the mechanisms over months or years.

Nonetheless, and even if the data obtained from the test were useful for comparing durability, we still cannot be 100% sure that this test will ensure that products exposed to the elements will deteriorate at this rate. It is a way of analysing how these materials behave when faced with the same aggression over a prolonged period of time.


We distinguish between two types of (ageing) study processes in laboratories (ISO 4892-2:2016):

  • Tests carried out using fluorescent UV radiation lamps: These lamps mimic the critical spectrum of short-wave ultraviolet (UV) radiation and reproduce the effect of sunlight on physical properties, such as surface degradation and resistance. 
  • Tests carried out with xenon arc lamps: These lamps are used to reproduce, as realistically as possible, the full spectrum of sunlight, including ultraviolet, visible light and infrared radiation.

Finally, it should be borne in mind that the exposure periods of these mechanisms will vary depending on the test. Their repeatability and reproducibility will vary according to the material to be measured and the test conditions.

In most cases, periodic evaluation will be needed to ensure the necessary changes based on the level and type of exposure, as well as the need for exposure to the full spectrum in order to provide an accurate simulation. The length of time that this material has been exposed during which a change occurred is the time that will be taken into account when it comes to classifying the durability of the materials.



The changes that materials exposed to ultraviolet radiation can undergo are wide ranging. These include:

  • Yellowing of the surface
  • Surface discoloration
  • Leaching of dyed plastics
  • Increased fragility due to loss of properties
  • Reduction in strength, elasticity and robustness
  • Onset of cracks

There are numerous other consequences that these mechanisms and their materials may suffer. So, we will now look into some possible solutions:

  • One of the most effective and inexpensive forms of protection is to use carbon black on these materials.
  • Others may include using fluoropolymers such as PTFE and PVDF.

However, unquestionably, the best way to protect against UV radiation is to use additives (stabilisers) or protective coatings such as paints.

¿What are additives?

These are substances that are incorporated into the mechanisms that will be subjected to the climatic conditions, providing them with resistance and adaptability to these conditions.

It is natural for some products to contain certain additives as part of their creation process, but sometimes this is not enough to withstand the elements.

The following are among the characteristics that these additives must have in order to be deemed suitable:

  • Must not hinder processing.
  • Must not lead to undesirable chemical interactions with other substances in the product itself.
  • Easy dispersion of the plastic.
  • Properly perform their function in accordance with the applicable regulations.
  • Improve the properties of natural resin.

Finally, some of the most common additives that are completely adequate for maintaining the mechanisms are as follows:

  • UV stabilising or anti-UV stabilising additives for plastics.
  • Antioxidant additive for plastics (stabilisers).
  • Antimicrobial additives for plastics/ Antibacterial additives for plastics.
  • Flame retardant additives for plastics.
  • Foaming agents.
  • Lubricant additive for plastics.

At Solera, we are constantly working on improving our mechanisms and the materials they are made of with the sole intention of providing our customers with the best products.

At Solera, we have a quality, social responsibility, environment and safety policy that is implemented in all our processes.

We regularly test our products to verify their durability and final level of quality.

As a result, we are able to guarantee the reliability and quality of our products. A commitment to quality that has been awarded certifications such as the AENOR, APPLUS, INTERTEK GS, IQNET and UL certifications.

Solera has an extensive range of mechanisms with UV protection. Mechanisms designed to be used outdoors and that are constantly exposed to the elements. Examples include Indubox , Polibox, Multuibox or the YBOX watertight junction boxes, among others.