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 has a long tradition of practical results, such as our current understanding of the stars, day and night, the seasons, and the phases of the Moon. Much of today's research in astronomy does not address immediate practical problems.Instead, it involves basic research to satisfy our curiosity about the universe and the objects in it. One day such knowledge may well be of practical use to humans.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.