Sharpness is a property inherent to razor blades. Therefore, careful handling is indeed necessary. Proper handling of the blade reduces the chance of cutting yourself. Not without reason did King Camp Gillette call his invention, a razor with interchangeable blades made at the beginning of the 20th century, "safety razor" - being much safer than the common shaving razors used during this time.
In general, a blade should be changed approximately after every 5 to 8 shaves - depending on your shaving behavior, the quality of the blades and growth of beard.
On MÜHLE safety razors, the blades slightly protrude on both short ends of the razor head and customers keep asking if this is meant to be and whether they can cut themselves with the protruding edges. Our answer is: yes, the blade is supposed to protrude and no, one cannot cut themselves as the edges are blunt. The protruding blade helps indicate that it has been inserted into the razor. Also, it is easier to grab here when changing the blades - no need to touch the cutting edge. When changing the blades, the safety razor should be facing downwards and be laid onto the table head first. In the next step, remove the handle, take off the lower part of the razor head, grab the blade with both thumb and index finger at the protruding end, then remove it and insert a new one.
The used blades shouldn't be thrown into the bathroom bin, collect them in a box instead. There are throwaway versions made of metal or - to meet the aesthetic demand - a reusable MÜHLE collecting box made of porcelain. This prevents cutting yourself with the old blades and makes for a more secure disposal of waste.