Standard kilogram no longer weighs a kilo

Standard kilogram no longer weighs a kilo

The cylinder metal that has long served as the international standard of a kilogram unit no longer weighs its namesake, according to

Over the years, the metal has accumulated micrograms through surface contamination which have tipped the scales past the original standard kilogram weight.

Platinum and platinum-iridium cylinders were made to create a standard definition of the kilogram and following the adaptation of the measurement as an international standard in 1875 around 40 countries were given the cylinders.

Now, however, each country now will be forced to define the kilogram separately, depending on the amount of micrograms their cylinder has acquired over the years.
Ultraviolet lights

But all is not lost. The kilogram is capable of returning to its glory days according to a recent study that revealed ozone and ultraviolet lights as possible methods for cleaning the cylinder.

The ozone and ultraviolet light treatment reportedly breaks the bonds between carbon atoms on the surface, cleaning away the extra micrograms.

While the carbon contamination may be washed away, the mercury that caused the contamination will remain.

The importance of micrograms, while seemingly insignificant, comes into play when weighing radioactive material, according to