Do the scales need to be ‘Approved’? Current law states that Medical scales as used in Hospitals, Doctors’ surgeries and Pharmacies etc. must be ‘Class III approved’ when used in relation to medication, treatment or diagnosis and have to display weight in Grams and Kilograms only. Scales for Health and Fitness Clubs, Slimming Clubs, Gymnasiums etc. do not need approval and usually allow display in Stones, Pounds and Ounces also if desired.