ðɪ ˌaɪpˌiːˈɛs nˈʌmbɚ ɹˈɛfɹəns tʊ ɐn ˌoʊdˈiː ɪz ðə sˈeɪm æz ðɪ ˌɛnpˌiːˈɛs nˈʌmbɚ, bˌʌt ðə skˈɛdʒuːlz wɜː lˈɪmɪɾᵻd tə stˈændɚd wˈɔːl ˌɛstˌiːdˈiː, ˈɛkstɹə stɹˈɔŋ, ˌɛksˈɛs ænd dˈʌbəl ˈɛkstɹə stɹˈɔŋ ˌɛksˌɛksˈɛs.
The IPS number (reference to an OD) is the same as the NPS number, but the schedules were limited to Standard Wall (STD), Extra Strong, (XS) and Double Extra Strong (XXS).