Five ampoules of early crystalline penicillin and one sample of undefined potency collected from Govt. agencies and industrial manufacturers in Britain and the USA by the Dept, of Biological Standards (DBS), National Institute for Medical Research Hampstead in 1944 in order to determine an International Standard.

Each of these glass vials of penicillin was collected from government agencies and industrial manufacturers in United Kingdom and the United States by the Department of Biological Standards at the National Institute for Medical Research in 1944 in order to establish an International Standard. Standardisation of drugs such as penicillin is important to ensure the quantity and quality produced is consistent all over the world.