Brick standard size and weight?

How come it's so hard to find the properties of a normal standard red clay brick that is used for construction? In Malaysia, is the brick produced different from other countries? How about the content of the brick? How to know what are the raw components and their composition in the brick? All in all the most important thing is the weight of the brick that the lecturer gonna give to us during the competition or are we allowed to bring our own brick? I think it's impossible because everyone might bring bricks of different size and weight, thus it wont be a fair competition. Maybe the lecturer won't mind or maybe she is not aware of the standard size? Asked dad and he told me that the standard size of the brick is 5" x 8" of weight around 2.8kg. However, the lecturer said the brick size is 5"x10". Thus, dad criticized that the lecturer know nothing about the standard size. Maybe he's right as once he is a contractor. anyhow, how come the internet unable to directly give the standardize properties of a brick? Or actually we don't have a standard properties as it depends on the brick to be used for what purpose?