The main purpose of our project is to be instructive and educational. However, since the display will be electrically powered, we will make sure that the final product will be safe for handling by children. Also, the customer has required that the product be washable, and painted in the colors of LEGO bricks. The product must be easily repairable.
To achieve safety when dealing with electricity, we will use a low-voltage power supply in our display (24VDC). Such electrical potential is not high enough to injure a person. Also, all of our electrical connections will be isolated and the circuit will contain a replaceable fuse. This will eliminate the possibility of an electrical short and fire.
To make the product washable, we decided to use rubber seats between the front panel and the electric lights, the kinds which are used on trailers. This is a good approach to making the components durable. The switches are going to be OK being wet, because our switches came with rubber boots which protect the gap between moving parts. Of course, the fan will be more sensitive to being soaked, but it will be fine to wash the grate with a damp rag.
In the last touches, we will paint the display in some LEGO colors (maybe blue and yellow).
As for repairability and maintenance, the product will be made of standard components, for example, trailer lights and cooling fan. This allows the display to be easily repaired if one part goes out, instead of scrapping the entire thing.