Use

Krypton is expensive to produce, which limits its use as an inert gas. It is used in a mixturewith argon to fill incandescent light bulbs, fluorescent lamps, lasers, and high-speed photographylamps. Radioactive Kr-85 is used as a source of radiation to measure the thickness ofindustrial materials. It is also used to test for “l(fā)eakage” of scientific instruments. Since 1960 the wavelength of the spectral lines of the krypton-86 isotope has been usedas the standard for the length of the meter. One meter is now defined as 1,650,762.73 wavelengthsof the reddish-orange spectral line of the Kr-86 isotope.