Safety razors are the next generation shaving tools because of their advance mechanics and design. They are known for their characteristic sharpness and durability but this doesn't give the Blades longevity. Just like other kinds of Blade, the Safety Razor becomes blunt over time. For this reason, blades are required to be changed occasionally. Some products like the Vikings Blade come with 5 extra blades to give users an uninterrupted shaving experience. There's no fixed time on when blades should be changed but factors such as these will help you out.
Thickness of the Hair
The thickness and coarseness of hair plays an important role in the Service Life of a safety razor blade. The thicker the hair, the greater the force required by the blade to cut the hair. While the original sharpness of the blade is not in doubt, the blade becomes dull quicker when subjected to that amount of pressure all the time.
Age of the Blade
An average safety razor has blades with service life of about 2 to 3 days. Quality safety products like the Vikings Blade have service life of about 5 to 7 days. This factor would also tell on the nearness of bluntness of the blade.
Frequency of Shaving
How often you take a shave will also affect the overall sharpness of the blade. For people with daily shaving, the blades will get blunted more easily than someone using a safety razor every 2 to 3 days.
