Agilent Technologies 5975C TAD VL MSD Troubleshooting And Maintenance Manual page 55

Table 5
Ions (m/z)
18, 28, 32, 44 or 14, 16
31, 51, 69, 100, 119, 131,
169, 181, 214, 219, 264, 376,
414, 426, 464, 502, 576, 614
31
43, 58
78
91, 92
105, 106
151, 153
69
73, 147, 207, 221, 281, 295, 355,
429
77, 94, 115, 141, 168, 170,
262, 354, 446
149
Peaks spaced 14 m/z apart
5975 Series MSD Troubleshooting and Maintenance Manual
Common contaminants
Compound
H 0, N , O
2 2
PFTBA and related ions
Methanol
Acetone
Benzene
Toluene or xylene
Xylene
Trichloroethane
Foreline pump oil or PFTBA
Dimethylpolysiloxane
Diffusion pump fluid and
related ions
Plasticizer (phthalates)
Hydrocarbons
General Troubleshooting
Possible source
, CO or N, O Residual air and water, air
2 2
leaks, outgassing from Vespel
ferrules
PFTBA (tuning compound)
Cleaning solvent
Cleaning solvent
Cleaning solvent
Cleaning solvent
Cleaning solvent
Cleaning solvent
Foreline pump oil vapor or
calibration valve leak
Septum bleed or methyl
silicone column bleed
Diffusion pump fluid
Vacuum seals (O-rings)
damaged by high
temperatures, vinyl gloves
Fingerprints, foreline pump oil
2
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