People can fall: â  from the edge of a completed roof; â  from the edge where work is being carried out; or â  through openings or gaps. Edge protection Unless the roof parapet provides equivalent safety, temporary edge protection will be required during most work on flat roofs.
Why is astronomy considered the original science? Astronomy is the oldest science for our ancients either drew or made structures according to seasons or movements of celestial bodies in our Universe.
Astronomy does have a impact on our life, rather it is an inseparable part of our life. It is the most effective branch of science. Being one of the primitive sciences, it talks about our origin, it describes about how our life began, yet, it is much more important and interesting than history and even much older!t is not only our past, but our ultimate future. With so much of problems here on Earth, it'll b essential 4 us in the future 2 include space travel in our daily schedule and spacecrafts as common vehicles. Thus, even if we try 2 ignore astronomy, it is one of the most significant studies of our world.