its fine and is safe to use BUT if you do not follow the correct procedures and use of equipment then you are taking a severe risk..........there is no point trying to shortcut as it WILL damage your health......there are lots of things that can affect your health if you do not follow the instructions...........stupid is as stupid does........SteveO & Cliff Read obviously take the correct procedures & use the correct equipment and should be congratulated for their work........regards from Oz, andyd