To set a dead time, inject 2.0 µL of a non-retained gaseous substance (compatible with the detector) via a standard 10 µL syringe with a PTFE-tipped plunger (cat.# 24557 or 24725) or draw 2 µL from the headspace over neat compounds. Accurately mark the injection starting time and peak elution time with an electronic integrator.
| Detector | Recommended Dead Volume Compounds |
| FID | methane, propane, butane |
| TCD | air*, methane, butane |
| NPD | acetonitrile headspace vapors, air* |
| ECD | air*, methylene chloride headspace vapors |
| ELCD | dichlorodifluoromethane or methylene chloride headspace vapors |
| MS | air*, propane, butane, argon |
| PID | acetylene ethylene |
* should be used only at lower oven temperatures
Some compounds may be slightly retained on thick-film phases (1.0 to 7.0µm) giving slightly erroneous dead volume times, however, they will be reproducible for similar column types.
