ɪt hˈæzbiːn θˈiəɹaɪzd ɔnðə bˈeɪsɪs ʌvðə θˈiəɹi ʌv ˌaɪsəbˈæɹɪk kˈaʊntɚdᵻfjˈuːʒən ðæt ˈɑːɹɡɑːn, bɪkˈʌz ʌv ɪts hˈaɪɚ məlˈɛkjʊlɚ mˈæs kəmpˈɛɹd wɪð nˈaɪtɹədʒən fˈoːɹɾi vˌiːˈɛs. twˈɛnti ˈeɪt jˈuː, mˈeɪ kˈɔːz lˈɛs ɪnˈɜːt ɡˈæs ˌɔnlˈoʊdɪŋ, ɪf jˈuːzd æz ɐ dˌiːkəmpɹˈɛʃən ɡˈæs, ɪnstˈɛd ʌv nˈaɪtɹoʊks.
It has been theorised on the basis of the theory of isobaric counterdiffusion that argon, because of its higher molecular mass compared with nitrogen (40 vs. 28 u), may cause less inert gas on-loading, if used as a decompression gas, instead of nitrox.