Dear fellows M2R R2R are 10yrs 15yrs old method as technology improves so do the reasearch progressed. Now RP power( i.e. Radiation )is not measured in R2R and M2R, it is measured in Roentgen. As every one cant have the mesuring instrument and people does not want to go in lab so at intial stages to confirm this radiation scientists dicovered battery test.The roentgen ( R , also röntgen ) is a unit of measurement for exposure to ionizing radiation (such asX-ray and gamma rays )