When an uncoated A1 object is exposed to (intensive) UV the very thin top layer of the A1 object will be affected (erosion) within a few months. This will mainly be noticeable by a change of the colour of the A1 object. After this initial period the erosion by UV will continue but at a very slow rate.
Adding sand to the A1 object (1 part A1 Liquid, 2 parts A1 Powder and 2 parts Quartz sand) will still result in an initial erosion of a very thin top layer but after this the added sand will almost stop the erosion process of the A1 object caused by UV.
For the best protection we advise applying layers of A1 Sealer PLUS to the A1 object as this layer will act as a barrier between the UV radiation and the A1. When you have used our A1 Sealer we recommend to apply a new layer after 3 years with our A1 Sealer PLUS. Other coating systems can be used as well if they are damp open (KEIM Soldalan) or the A1 object can release its moist at the backside of the A1 objects (for ventilated Cladding systems).