ðə klˌæsɪfɪkˈeɪʃən sˈɪstəm wʌz fˈɔːɹmɚli ɪŋklˈuːdᵻd ɪnðə mˈænjuːəl ʌv pɹətˈɛktɪv sᵻkjˈʊɹɹᵻɾi ˌɛmpˌiːˈɛs wˌɪtʃ spˈɛsᵻfˌaɪd ðɪ ˈɪmpækt ʌv ɹᵻlˈiːs ænd pɹətˈɛkʃən lˈɛvəl ɹᵻkwˈaɪɚd fɔːɹ ˈiːtʃ klˌæsɪfɪkˈeɪʃən.
The classification system was formerly included in the Manual of Protective Security (MPS) which specified the impact of release and protection level required for each classification.