plˈæstɪk sˈɪntɪlˌeɪɾɚz ɑːɹ ˈɔfən jˈuːzd tə ɹᵻdʒˈɛkt tʃˈɑːɹdʒd pˈɑːɹɾɪkəlz, wˌaɪl θˈɪkɚ sˌiːˈɛs ˈaɪ, bˈɪsmʌθ dʒˈɜːmɐnˌeɪt"bˌiːdʒˌiːˈoʊ", ɔːɹ ˈʌðɚɹ ˈæktɪv ʃˈiːldɪŋ mətˈɪɹiəlz ɑːɹ jˈuːzd tə dɪtˈɛkt ænd vˈiːɾoʊ ɡˈæmɚɹˈeɪ ᵻvˈɛnts ʌv nˈɑːŋkˈɑːzmɪk ˈɔːɹɪdʒˌɪn.
Plastic scintillators are often used to reject charged particles, while thicker CsI, bismuth germanate ("BGO"), or other active shielding materials are used to detect and veto gamma-ray events of non-cosmic origin.