Residual gas analysis in the main chamber of ISAC. The total gas pressure measured by a Bayer-Alpert gauge was 3.6 × 10^-11 mbar. The intensity scale on this plot corresponds approximately to pressure in mbar units. The most abundant species are H₂ (m/z = 2), H₂O (m/z = 18), CO/N₂ (m/z = 28), CH₃OH (m/z = 31), and CO₂ (m/z = 44). The level of organic contaminants, toluene, or xylene at m/z = 91 and 92, is below 10^-13 mbar.